Saudi and American officials are investigating the possibility that attacks on Saudi oil facilities Saturday involved cruise missiles launched from Iraq or Iran, questioning Yemeni rebel claims of responsibility, people familiar with the matter said.

Leaders of the Houthis, the Yemeni rebels whom Saudi Arabia is trying to dislodge from the country’s capital, claimed they sent a squad of drones hundreds of miles into the heart of Saudi Arabia to carry out coordinated attacks on two of the country’s vital energy sites. If true, the attacks marked the most effective and far-reaching drone strikes carried out by outgunned Houthi forces in neighboring Yemen.

But officials around the globe investigating the attack questioned the Houthi claims and suggested the strike may have come from Iraq or Iran, to the north, rather than Yemen, to the south. Iran supports a host of Shiite militias in Iraq.

Secretary of State Mike Pompeo said in a tweet that “there is no evidence the attacks came from Yemen” and accused Tehran of launching “an unprecedented attack on the world’s energy supply.”

The Saudi Interior Ministry said Saturday that the facilities were hit by a drone attack, an account confirmed by people familiar with the strikes.


But Persian Gulf officials said experts were examining the possibility that the attackers used cruise missiles, either instead of or along with drones.

A strike on Saudi facilities from Iraq isn’t without recent precedent.

Earlier this summer, U.S. officials concluded that a May 14 drone attack on Saudi Arabia’s pipeline was launched from Iraq, not Yemen. At the time, Mr. Pompeo urged Iraq’s prime minister to contain the threat posed by Iran-backed forces in the country.

If Tehran carried out the attack directly, it would pose a new national security challenge for President Trump, who could be pressed to respond by striking Iran. In June, Mr. Trump called off a strike on Iran and suggested he is willing to talk.


And the use of cruise missiles rather than drones would suggest an escalation in the conflict beyond drones.

In recent months, Houthi forces have used a new type of cruise missile to hit Saudi Arabia at least three times, according to people familiar with the investigation.

In July, Houthi forces unveiled the new type of cruise missile, called Quds, saying it could fly more than 900 miles and would help change the course of the war. At the same time, the Houthi fighters unveiled a new drone they said had the same range.

This summer, two of the cruise missile strikes hit Abha airport in southwest Saudi Arabia, close to the Houthi-controlled Yemen border. A third hit a desalinization plant in the same part of the country.


No matter who carried out Saturday’s attack, and where it came from, U.S. and Saudi leaders are likely to point the finger at Tehran, which provides varying degrees of support to allies in Yemen and Iraq.

Saturday’s attack is likely to deliver another setback to American attempts to open direct talks with Houthi leaders in an effort to end the four-year-old war in Yemen that has fractured as the United Arab Emirates withdrew most forces from the fight and its allies on the ground opened a new front by battling Saudi-backed forces.

Houthi leaders rebuffed American efforts to launch the talks earlier this month after Saudi-coalition airstrikes hit a detention center, killing dozens.

Write to Dion Nissenbaum at dion.nissenbaum@wsj.com, Summer Said at summer.said@wsj.com and Nancy A. Youssef at nancy.youssef@wsj.com