Five civilians were killed in US attacks on cargo boats, Iran's semi-official Tasnim news agency reported Tuesday.

Following the claim by the US military that it had targeted six Iranian speedboats, and given that none of Iran's combat vessels were hit, local sources were consulted to verify the nature of the incident, said the report.

It was determined that US forces had attacked two small civilian cargo boats, which were traveling from Khasab along the Omani coast toward Iran, killing five civilian passengers onboard, it said.

Brad Cooper, chief of US Central Command, said on Monday that the U.S. military had sunk six Iranian small boats in the Strait of Hormuz.

The Iranian boats were struck by US Apache and MH-60 Seahawk helicopters, Cooper told a news conference.