On September 14, an explosive drone attack damaged a processing facility and oil field in Abqaiq and Khurais, Saudi Arabia. The Houthi rebel movement in Yemen claimed responsibility for the attack, although U.S. and Saudi officials claimed the attacks originated outside of Yemen. Both countries blamed Iran. Tehran has been widely accused of providing the Houthis with weapons, training and financial support.
The current conflict between Saudi Arabia and the Houthis started in March 2015. Riyadh initiated airstrikes in Yemen on behalf of the government led by President Abd Rabbuh Mansour Hadi, which was ousted from Sanaa by the Houthis. The first cross-border attack by Houthis was in May 2015 in response to the Saudi-led intervention. Houthi rebels shelled the city of Najaran, killing three and shutting down flights to and from the airport. The Houthis have continued to launch scores of cross-border attacks, using ballistic missiles and explosive drones to hit targets inside Saudi Arabia.
May 5: The Houthis fired mortars into the Saudi city of Najran. The attack killed three people and forced Saudi Arabia to close the local airport.
June 6: Saudi Arabia intercepted a Scud missile fired by the Houthis in retaliation for coalition airstrikes in Yemen. The missile was shot down by a Patriot missile battery near Khamis Mushait.
July 20-24: Saudi media reported five consecutive days of cross-border incidents. The sources reported clashes at the al Tuwal border crossing and projectiles fired from Yemen into Jizan and Najran provinces.
Aug. 19: Houthi-controlled television broadcast images of fighters allegedly crossing the border into Saudi Arabia.
Aug. 26: Pro-Houthi Yemeni army units fired a Scud missile into Saudi Arabia. The Saudi military said the missile targeted an electricity station in Jizan province but was intercepted.
Oct 15: The Houthis fired a Scud missile across the border near Khamis Mushait. Saudi warplanes bombed missile launchers in Sana’a in response.
Dec. 31: Saudi civil defense authorities claimed three civilians were killed in Saudi Arabia from cross-border missile attacks.
Feb. 1: Saudi outlet Al-Arabiya reported a Houthi-launched rocket from Yemen that killed a child and wounded nine other civilians in Najran.
July 30: Houthi fighters reportedly attempted to cross the border near Najran but were killed by Saudi warplanes.
Aug. 16: Cross-border shelling by the Houthis killed seven civilians in Najran, according to Saudi state television.
Aug. 28: A Houthi-fired rocket killed two girls in Najran following the collapse of peace talks over the conflict in Yemen.
Sept. 24: A senior Houthi military officer was killed while trying to infiltrate Najran, according to Reuters.
Oct. 10: The Houthis launched a ballistic missile at the Taif military base in Saudi Arabia. The attack was in response to a coalition airstrike that killed 140 mourners at a funeral in Yemen. The projectile was intercepted before its target but went further than any other missile launched from Yemen had previously.
Oct 28: Saudi Arabia said it intercepted a missile near Mecca. The Houthis denied they had fired the missile and said they would “not target holy areas.”
Nov. 18: Saudi’s Interior Ministry said a soldier was killed by a cross-border missile attack just hours before a 48-hour ceasefire was set to begin.
Dec. 9: Saudi state media reported a Saudi border guard was killed by a landmine on the country’s southern border.
Dec 31: Saudi’s Interior Ministry said a soldier was killed in cross-border fire with the Houthis.
Jan. 30: Three Houthi suicide boats attacked a Saudi frigate off the Hodeida port in the Red Sea. Two crew members were killed and another three were injured.
Jan. 31: The Houthis’ official news agency said they launched a ballistic missile at a Saudi-led coalition military base on the Red Sea island of Zuqar on Monday, countering the Saudi claim of a suicide attack.
May 19: They Houthis said they fired a ballistic missile towards Saudi Arabia’s capital Riyadh. The Saudi-led coalition said it intercepted the missile 200 km west of the city.
July 22: The Houthis fired a Burkan-2 ballistic missile at an oil refinery in Saudi Arabia.
July 26: Houthi rebels launched a Scud missile toward an oil facility near the port city of Yanbu in Saudi Arabia.
Nov. 4: Saudi Arabia said it intercepted a ballistic missile that was fired from Yemen near King Khaled Airport in Riyadh.
Nov. 6: Saudi Arabia blamed Iran for the Houthi missile attack on Riyadh airport.
Nov. 12: The Houthis threatened to attack warships and oil tankers in retaliation for Saudi Arabia closing Yemen’s ports.
Dec. 19: Saudi Arabia intercepted a ballistic missile over southern Riyadh. The Houthis claim responsibility for the attack, which targeted the royal Yamama Palace in the capital. No damage was reported.
Jan. 5: Saudi Arabia claimed to intercept a ballistic missile over the border region of Najran. The Houthis claimed responsibility for the attack.
Jan. 9: Houthi rebels threatened to block the Red Sea shipping lane if the Saudi-led coalition kept moving towards the Hodeidah port. “If the aggressors keep pushing toward Hodeidah and if the political solution hits wall, there are some strategic choices that will be taken as a no return point, including blocking the international navigation in the Red Sea,” said the Houthi political council chief, Saleh al Samad.
Jan. 10: The Saudi-led coalition said it foiled an attack on a Saudi oil tanker by Houthi fighters near the Hodeidah port. The coalition destroyed a boat carrying explosives headed towards the tanker, according to coalition spokesman Colonel Turki al Maliki.
Jan. 11: The Houthis fired a ballistic missile at a special forces camp and a facility for helicopter gunships in the Saudi border province of Najran. Saudi air defense forces shot down the missile mid-air without any casualties, said Colonel al Malki.
Jan. 16: Houthi rebels said they fired a short-range ballistic missile toward a regional airport in the Saudi border province of Jizan. Saudi defense forces said they shot down the missile.
Jan. 18: The Houthis fired a missile into the border province of Najran in Saudi Arabia. The missile targeted an air defense operations center and inflicted heavy damage to an air defense base in the Khadhra crossing point in Najran.
Jan. 30: The Houthis said they fired a long-range ballistic missile at King Khaled International Airport in Riyadh. It was the second time the Houthis targeted the airport.
Feb. 14: The Saudi military repelled a cross border attack by Houthi rebels in the southern border town of Nahran. Around 25 Houthi militants were killed with more wounded. Saudi helicopters also destroyed three Houthi military vehicles. It was the second cross border attack by the Houthis in less than a week.
March 25: The Houthis fired seven missiles at four Saudi cities - three at the capital Riyadh, one at the southwest city of Khamis Mushait, one at southern Najran and two at Jizan. The Houthi Ministry of Defense claimed the missiles hit seven different targets, including four airports. But the Saudi coalition said all missiles were intercepted and destroyed. Fragments from the intercepted missiles killed an Egyptian resident. It was the first death on Saudi soil since the military intervention began in 2015.
March 29: Houthi rebels fired a ballistic missile from the northern Yemeni province of Saada at the Saudi city of Jizan. Saudi air defenses intercepted the missile before it could strike its target.
March 31: Saudi air defense forces intercepted a missile fired by the Houthis. The missile targeted a Saudi National Guard base in the southern city Najran, a rebel-run news agency reported. An Indian resident was injured by falling debris in the attack.
April 3: Houthi rebels struck a Saudi oil tanker with a missile west of Hodeidah in international waters. A coalition warship intervened and escorted the tanker, which sustained minimal damage, northwards. The Houthis said the attack was in response to a coalition airstrike on the rebel-held Hodeidah port that killed 14 people, including women and children, the day before.
April 4: Saudi Arabia intercepted a Houthi missile that was intended for southern Jizan.
April 6: The Houthis fired a missile at the southern city Najran, Saudi Arabia. Saudi defense forces intercepted the missile. No damage or casualties were reported.
April 11: The Houthis launched a Burkan 2-H ballistic missile at the Saudi capital Riyadh and also targeted oil facilities in southern Najran and Jizan, according to the rebel's Al Masirah television network. The missile traveled more than around 500 miles into Saudi Arabia before it was intercepted by Saudi air defenses. The Saudi-led coalition said it had also shot down two drones in southern Saudi Arabia. The Houthis claimed they targeted some areas with Qasif-1 drones.
April 12: Saudi air defense forces intercepted a Houthi missile targeting southern Jizan.
April 13: The Houthis fired a missile at Saudi Arabia for a third day in a row. The missile targeted Jizan but was intercepted by Saudi defense systems.
April 22: The Houthis fired a ballistic missile at southern Najran. Saudi air defenses intercepted the missile, "but the shrapnel scattered over residential areas and cause a fire at a farm belonging to a citizen, without causing any injuries," the Saudi Press Agency said.
April 23: Saudi Arabia intercepted two ballistic missiles at an Saudi Aramco oil production facility in southern Jizan. The Houthis claimed responsibility.
April 26: Saudi Arabia intercepted four Houthi ballistic missiles over southwestern Jizan. Falling debris from the interception killed one person.
April 29: The Houthis vowed to intensify rocket attacks on Saudi Arabia and said they were manufacturing their own ballistic missiles. Three Saudi soldiers died in clashes with the Houthis along the Yemen-Saudi Arabia border, the Saudi Press Agency said.
May 6: Houthi rebels launched two ballistic missiles at the southern city of Najran. Saudi air defense forces intercepted the missiles. Debris from the missiles fell on residential neighborhoods but no injuries or damage were reported.
May 9: The Houthis fired missiles at economic targets in Riyadh. Saudi Arabia intercepted one missile, and another landed in an uninhabited area in the desert south of the capital. Col. Al Maliki said the Houthis also “failed to launch a short-range Badr-type rocket” toward Najran but it also landed in an desert area.
May 14: Houthi rebels launched a ballistic missile at a Saudi Aramco facility in southern Jizan province. The missile landed in the open desert and no damage was inflicted, the Saudi-led coalition said.
May 19: Saudi Arabia intercepted ballistic missiles from the Houthis, which were targeting the city of Khamis Mushait.
June 10: Saudi Arabia intercepted a missile fired at Jizan, according to Saudi state media.
June 24: Saudi Arabia said it intercepted and destroyed two missile targeting Riyadh. The Houthis said the missiles were intended for the Saudi Ministry of Defense
July 18: Saudi Arabia intercepted a missile fired at Najran, according to al-Arabiya.
July 19: Saudi Arabia intercepted a second ballistic missile fired at Jizan, according to al-Arabiya.
July 25: The Houthis attacked a Saudi oil tanker in the Red Sea, slightly damaging it.
Aug. 6: Saudi Arabia intercepted a ballistic missile fired at Najran by the Houthis, according to al-Arabiya.
Aug. 9: Shrapnel from an intercepted ballistic missile killed a man and wounded 11 others. The missile was fired at the southern Saudi city of Jizan.
Sept. 2: Saudi Arabia claimed it intercepted a ballistic missile launched toward Jizan by the Houthis.
Sept. 30: Saudi Arabia said it foiled an attack by explosive remote-controlled boats against the Jizan port.
Nov. 18: The Houthis said they would halt missile and drone attacks on Saudi Arabia in response to U.N. mediation efforts in Yemen.
Nov. 29: The Houthis fired at Najran in response to what it claimed were violations of a U.N.-brokered ceasefire.
Feb. 17: The Houthis said they conducted a major cross-border offensive, a major breach of the U.N.-brokered agreement in Stockholm. Saudi Arabia said nine soldiers were killed in the fighting.
April 2: Saudi Arabia intercepted two Houthi drones launched toward Khamis Mushait. Five civilians were injured by the debris, according to the coalition.
April 8: Saudi Arabia intercepted a drone launched toward Asir City, according to Al-Arabiya.
May 14: A drone attack by the Houthis damaged two oil pumping stations over 200 miles from Riyadh. Saudi Arabia paused oil pumping through the east-west pipeline in response to the attack.
May 20: Saudi Arabia said it intercepted two missiles fired at Mecca province. The Houthis denied the missiles were intended for Mecca.
May 21: The Houthis claimed responsibility for a drone attack against Najran airport, claiming to strike an arms depot in the airport. Coalition spokesman Col. Al Maliki said the Houthis “had tried to target” a civilian site as well.
June 11: Two Houthi drones were launched at Khamis Mushait. The Saudi Press Agency said the drones were intercepted.
June 12: The Houthis launched a cruise missile against Saudi Arabia’s Abha airport, injuring 26 people. Saudi Arabia accused Iran of being behind the attack.
June 19: The Houthis fired a missile targeting a Red Sea desalination plant in al Shuqaiq but caused no casualties.
June 20: Saudi Arabi said it intercepted a drone aimed at the Jizan airport.
June 23: The Houthis hit the Abha airport with a drone, killing one and wounding 21 others.
June 30: Saudi Arabia said it intercepted two drones launched at Jizan and Asir.
July 2: The Houthis conducted another drone attack against Abha airport, wounding eight Saudis and one Indian national.
August 5: The Houthis claimed they disrupted air traffic with drone attacks on Abha and Najran airports. A spokesperson for the coalition denied either airport had been hit.
August 25: The Houthis fired 10 ballistic missiles at Jizan airport, killing and wounding dozens. Saudi Arabia said it intercepted at least six missiles.
August 26: The Houthis claimed to hit a military target in Riyadh with an armed drone, but Saudi Arabia denied that the attack occured.
Sept. 14: A major drone attack hit an Aramco facility and oil field in Abqaiq and Khurais, over 500 miles from Yemen. The Houthis claimed responsibility for the attack, which they said involved 10 drones.
Sept. 15: Secretary of State Mike Pompeo accused Iran of being behind the Abqaiq attack, claiming “there is no evidence the attacks came from Yemen.”
Tehran is behind nearly 100 attacks on Saudi Arabia while Rouhani and Zarif pretend to engage in diplomacy. Amid all the calls for de-escalation, Iran has now launched an unprecedented attack on the world’s energy supply. There is no evidence the attacks came from Yemen.— Secretary Pompeo (@SecPompeo) September 14, 2019
Sept 16: The United States reportedly told Saudi Arabia it believed Iran was the staging ground for the Abqaiq attacks. Coalition spokesman Col. al Malki said the attacks were not launched from within Yemen.
Andrew Hanna, a research assistant at the U.S. Institute of Peace, contributed to this timeline.