WASHINGTON — Iranian-backed Houthi rebels in Yemen have ramped up drone and missile attacks on Saudi Arabia over the past month, employing increasingly sophisticated drones and missiles to hit targets across the kingdom's territory, Defense officials and experts say.
The Houthis launched more than 40 drones and missiles at Saudi Arabia in February alone, a senior U.S. Defense official told NBC News.
"We're certainly aware of a troubling increase in Houthi cross-border attacks from a variety of systems, including cruise missiles, ballistic missiles and UAVs (unmanned aerial vehicles)," the Defense official said.
The attacks underscore the Houthis' ability to strike at far-flung targets in Saudi Arabia over hundreds of miles, including the center of the kingdom's oil industry.
But unlike a devastating drone and cruise missile attack in September 2019 that knocked out two crucial oil plants, Saudi Arabia has managed to shoot down many of the incoming drones and missiles.
In their latest attack on Saudi Arabia on Sunday, Houthi forces said they launched a medium-range Zulfiqar missile and 10 armed drones at the eastern cities of Ras Tanura and Dammam, home to key oil facilities, and seven short-range Badr missiles and four drones at targets in the south.
As a result of the growing threat from the air, the U.S. military has stepped up assistance to the Saudis, sharing intelligence to help them spot and intercept explosive-laden drones and an array of ballistic and cruise missiles, Defense officials said.
Saudi Arabia said Sunday's attacks caused no casualties or major damage to the country's oil installations.
Although the Saudis have succeeded so far in foiling recent attacks, there have been close calls. On Feb. 11, Houthi rockets struck Abha International Airport in southwestern Saudi Arabia, causing a fire on a civilian airliner, though no one was injured.
After the September 2019 attack that disrupted more than half the kingdom's oil production for days, the United States provided Patriot missile defense batteries to Saudi Arabia as well as a Terminal High Altitude Area Defense, or THAAD, system, to help Riyadh fend off the Houthi threat.
The anti-missile systems, however, are designed to track and hit missiles coming in at a higher altitude, and low-flying drones provide a more challenging target, particularly when launched in higher numbers. The Saudis have turned to using U.S-made F-15 fighter jets armed with missiles to go after the drones, according to Defense officials and regional experts.
Saudi Arabia's embassy in Washington did not respond to requests for comment.
Iranian arms and advice
The scale and reach of the Houthi attacks illustrates how the rebels have progressed as a fighting force since the start of the Yemen war in 2015, and just how much they have benefited from Iranian arms and advice, according to regional analysts and U.N. experts.
A January U.N. report said there were growing indications that Iran was providing arms and weapons components to the Houthi rebels via smuggling routes at sea.
"An increasing body of evidence suggests that individuals or entities in the Islamic Republic of Iran supply significant volumes of weapons and components to the Houthis," the U.N. panel of experts report said.
Previous U.N. reports have found that ballistic missiles fired by the Houthis were manufactured by Iran, and that drones used by the Houthis were nearly identical in design and capability to those produced by Iran.
The Houthis have proven adept at putting Iranian-supplied components — including drone engines, rocket motors and electronics — to use in manufacturing missiles and drones at local plants, said Michael Knights of the Washington Institute for Near East Policy. Iranian-backed Lebanese Hezbollah operatives have also aided the effort, he said.
"The Houthis with Iranian support and Lebanese Hezbollah support have managed to pull together some pretty amazing strike capabilities," said Knights, whose research has focused on Iranian and Houthi military capabilities.
"They've got their production up to the level where they can release much more of these systems. They've reached technical maturity on their local production systems," Knights said.
Iran has repeatedly denied arming the Houthi forces. Iran's U.N. mission did not respond to a request for comment.
Iran is the only country that has recognized the Houthi forces as the government of Yemen, and its envoy to the rebels, Hassan Irloo, was described by the State Department as an officer in the Islamic Revolutionary Guards Corps.
The war in Yemen, which broke out in 2015, pits Shiite Houthis aligned with Iran against a U.S.-supported Saudi-led coalition of Sunni Muslim states that want to see the internationally recognized government restored to power. The civil war also has become a proxy conflict between Saudi Arabia and Iran.
The Houthi air attacks on Saudi Arabia have been coupled with a ground offensive in Yemen around Marib, the last northern stronghold of the internationally recognized Yemeni government. U.N. officials have warned the fall of Marib could displace hundreds of thousands of Yemenis, aggravating what aid agencies call the world's worst humanitarian crisis.
The Houthi assault on Marib and missile salvoes on Saudi Arabia coincide with a renewed international effort to try broker a peace settlement, with a U.S. envoy, Tim Lenderking, wrapping up 17 days of talks in the region this week. Lenderking spent extra time in the region trying to secure a ceasefire and “while there is some hopeful progress, more commitment is needed from the parties,” the State Department said Thursday.
At an event Friday in Washington, Lenderking said a “sound plan” for a ceasefire that Saudi Arabia supports was now before the Houthi leadership. But “tragically and somewhat confusingly,” the Houthis appear to be putting a priority on an offensive on Marib, Lenderking said at a virtual briefing organized by the Atlantic Council think tank.
The United States along with France, Germany, Italy and Britain on Thursday condemned the Houthi offensive on Marib and the "major escalation of attacks the Houthis have conducted and claimed against Saudi Arabia," the governments said in a statement Thursday.
The military push by the Houthis appears aimed at gaining leverage before any possible peace talks, and exploiting friction between the Biden administration and the Saudis, said Adel Abdel Ghafar, a fellow from the Brookings Doha Center think tank.
"The Houthis have been emboldened by the Biden administration's decision to not support the Saudi-led war on Yemen," Ghafar said, and are seeking to put themselves "in a stronger position once negotiations start to end the war."
President Joe Biden cut off support for Saudi Arabia's military campaign in Yemen shortly after entering office, and his administration lifted a terrorist designation on the Houthi rebels, saying it was hindering emergency aid deliveries to a country on the verge of famine. Democrats in Congress for years had demanded an end to U.S. backing of the Saudi-led war, citing air strikes using U.S.-made bombs that inflicted heavy civilian casualties.
But critics have accused the Biden administration of sending the wrong signal to the Houthis, and that the rebels have little incentive to make concessions.
"Pressuring Riyadh while essentially giving the Houthis a free pass has created an asymmetry that no amount of shrewd shuttle diplomacy is likely to overcome," said Brad Bowman, a former national security policy adviser to Republican senators and now senior director at the Foundation for Defense of Democracies think tank.
The Biden administration has condemned the Houthi attacks on Saudi Arabia and recently announced new sanctions on two Houthi military leaders, vowing to "keep up the pressure" on the rebels.
Bowman argued the administration should move to interdict arms shipments to Yemen, depriving the Houthis of a steady supply of weapons.
"Blocking access to key weapons and technology from Iran might increase the incentives for the Houthis to come to the negotiating table in good faith," Bowman said.
Charlene Gubash reported from Cairo.