Iran live updates: 1st purported message from new supreme leader read on state TV

The Iranian military claimed on Thursday to have struck a vessel owned by a U.S. company off the Iraqi coast in the Persian Gulf, saying it targeted the "Safesea Vishnu" after the vessel "disobeyed and ignored the warnings" of the Iranian navy.

That oil tanker, which was sailing under a Marshall Islands flag, was identified by Iraq's state oil company as one of two hit with projectiles in the country's territorial waters early on Thursday.

The other ship struck nearby was the "Zefyros," a Maltese-flagged oil and chemical tanker, Iraq said. Iran did not claim responsibility for that apparent attack.

Both ships were hit with projectiles that resulted in fires onboard, according to U.K. Maritime Trade Operations, a tracking organization.

Videos verified by ABC News show flames engulfing the "Safesea Vishnu" as the crew of an adjacent vessel throw rubber rings to people in the water.

A third ship was also struck Thursday morning off the coast of the United Arab Emirates, near the Strait of Hormuz, the UKMTO organization said. Iran also did not claim responsibility for that strike.

Iran's Islamic Revolutionary Guard Corps said in a statement announcing the "Safesea" strike that it was policing the gulf and strait to ensure vessels "act in accordance with the laws and regulations" that Iran has put in place "in order to remain safe from being hit by stray projectiles."

-ABC News' Helena Skinner and Somayeh Malekian

A ship was reported to have been hit early on Thursday by a projectile near the Strait of Hormuz, a few hours after two ships were similarly struck in the Persian Gulf off the coast of Iraq, according to the U.K. Maritime Trade Center, a tracking organization.

The vessel was struck by an "unknown" projectile 35 nautical miles north of Jebel Ali, the United Arab Emirates, causing a small fire on board, according to the UKMTO.

Two tankers were also hit in the early hours of Thursday morning by "unknown" projectiles, leading to fires on board both ships, the UKMTO said in an earlier alert and update.

The vessels were hit off the coast approximately 5 nautical miles south of al Basrah, Iraq, according to the UKMTO. All crew members were evacuated, the organization said.

-ABC News' Zoe Magee

Pentagon officials told a group of senators in a closed-door briefing on Tuesday that the war in Iran cost at least $11.3 billion in its first six days, three people familiar with the briefing told ABC News.

The New York Times first reported the briefing and the $11.3 billion figure.

Senators on the Defense Appropriations subcommittee received the briefing, a source confirmed. Sen. Chris Coons, the top Democrat on that subcommittee, told reporters on Wednesday that the $11.3 billion estimate he had seen publicly reported was "roughly accurate."

"I expect that the current total operating number is significantly above that," Coons said when pressed on whether that figure took into account things like military buildup.

Coons also said that while the cost per day is not a "steady state," to "assume that it is well above a billion and a half a day I think would be a fair guess."

The money that has so far been spent to fund operations in Iran comes out of Pentagon funds already allocated by Congress. Congress has not yet approved any additional funding for Iran, and lawmakers on both sides of the aisle say that the White House has not yet made a request for supplemental funding.

The Department of Energy announced today that it has been authorized by President Donald Trump to release 172 million barrels from the U.S. Strategic Petroleum Reserve, starting next week, in an effort to lower gas and oil prices amid the war in Iran.

"This will take approximately 120 days to deliver based on planned discharge rates," Energy Secretary Chris Wright said in a statement Wednesday.

The statement added that this was part of the International Energy Agency's agreement announced earlier Wednesday to coordinate the release of 400 million barrels of oil.

In an interview with local CBS affiliate WKRC in Ohio earlier Wednesday, Trump said that they would tap into the Strategic Petroleum Reserve in an effort to bring gas and oil prices down.

"Well, we'll do that, and then we'll fill it up. I filled it up once, and I'll fill it up again. But right now, we'll reduce it a little bit, and that brings the prices down," Trump said.