The initial findings of a team of U.S. military experts have revealed that Iran or Iranian-sponsored proxies were likely behind a sabotage attack on two Saudi oil tankers and two other vessels in the Gulf of Oman on Sunday.

The exact details of the attack remain unclear, but investigators believe that Iranian agents or one of Tehran’s regional proxies used explosives to blow large holes in the ships.

U.S. officials said that each of the vessels had a 5- to 10-foot hole in it, near or just below the water line. They were not authorized to discuss the results of the investigation and spoke on condition of anonymity.

Saudi Arabia confirmed on Monday that two of its oil tankers were among those attacked off the coast of the United Arab Emirates in an attempt “to undermine the freedom of maritime navigation” and “the security of oil supplies” around the world.

Although the kingdom stopped short of blaming Iran for the incident, Saudi officials stressed it was the responsibility of the international community to hold accountable those behind the attack.

The incident happened 140 kilometers south of the Strait of Hormuz, the world’s most sensitive oil transportation choke point. The U.S. has warned that “Iran or its proxies” could be targeting maritime traffic in the region.

U.S. President Donald Trump said Monday, “It’s going to be a bad problem for Iran if something happens,” after Washington deployed an aircraft carrier strike group and four B-52 bombers to the region at a time of rising tensions with Tehran.

Iranian officials have denied any involvement in the attacks and have blamed Israel for trying to inflame military tensions between Iran and the United States.

The Islamic Republic News Agency (IRNA) on Tuesday quoted an Iranian parliamentary spokesman as saying that, “The events that took place in the Emirates were Israeli mischief.” Behrouz Nemati provided no details on what role Israel may have played in the incident.

[Photo: ABC News / YouTube]