The U.S. military is currently striking Iran in a new round of attacks Wednesday night, military officials said.

The fresh attacks come hours after President Trump said he thought a three-week-old cease-fire between the two countries was “over.” Iranian state media reported that explosions had been heard in at least three port cities along the country’s southeastern coast.

The latest strikes, the U.S. Central Command said, were intended to undercut Iran’s ability to threaten ships in the Strait of Hormuz, a critical waterway for global energy supplies that has become a key issue in the conflict. The U.S. military called the attacks retaliation for “recent unjustified aggression against commercial shipping and civilian crews.”

But Mr. Trump said earlier Wednesday that while the United States would probably hit Iran “hard,” he did not expect a return to all-out war. “I don’t think it’s going to start again. I think it’s going to go very quickly,” he told reporters at a NATO summit in Turkey.

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