Tensions rise at sea between Iran and the U.S.

Eleven vessels from Iran's Revolutionary Guard navy came dangerously close to six U.S. Navy and Coast Guard ships in the Gulf.

That's according to the U.S. military, who called the moves "dangerous and provocative" on Wednesday (April 15).

At one point, the Iranian vessels came within 10 yards of the U.S. Coast Guard.

The U.S. ships responded with several warnings, blasting the ships' horns and radio calls.

After about an hour the Iranian ships left, said the U.S. military in their statement.

This incident comes at a time of increased tensions between the two countries.

Earlier this year the U.S. killed Iran's top military general, Qassem Soleimani, in a drone strike.

Iran then retaliated with a rocket attack on a base in Iraq where U.S. forces were based.

A Hong Kong tanker was also briefly detained in Iran on Wednesday, after armed Iranian guards in speedboats directed the vessel into its waters.