WASHINGTON/ISLAMABAD –

At least two merchant vessels reported they were hit by gunfire as they attempted to cross the Strait of Hormuz on Saturday, three maritime security and shipping sources said, shortly after Iran said it was once more tightening control of the waterway.

Some merchant vessels received a radio message from Iran’s navy that the vital energy chokepoint was shut again and no ships were allowed to pass through, shipping sources said.

Earlier, ​maritime trackers showed a convoy of eight tankers transiting the waterway in the first major movement of ships since the U.S.-Israeli war on Iran began seven weeks ago.