A U.S. destroyer intercepted two oil tankers attempting to leave Iran and forced them to turn back.

The ships came from Chabahar port in the Gulf of Oman, according to Reuters, which cited an unnamed source. 

The ships were contacted via radio, after which the ships complied with the U.S. blockade of the Strait of Hormuz that Trump had enacted on Monday. 

U.S. Central Command said on Tuesday that 10,000 U.S. sailors, marines and airmen, as well as dozens of warships and aircraft, are executing the blockade, and in its first 24 hours, no ships had managed to squeeze through it. 

Six merchant vessels, CENTCOM added, complied with direction from U.S. forces to return to the Gulf of Oman.