U.S. forces struck missile launch sites in Iran and boats trying to "emplace" mines, a U.S. official said Monday night.

U.S. Central Command characterized the strikes in southern Iran as defensive and said they were to "protect our troops from threats posed by Iranian forces," according to The New York Times.

“U.S. forces conducted self-defense strikes in southern Iran today to protect our troops from threats posed by Iranian forces," U.S. Central Command spokesperson Capt. Tim Hawkins said. "Targets included missile launch sites and Iranian boats attempting to emplace mines. U.S. Central Command continues to defend our forces while using restraint during the ongoing ceasefire."

Hawkins also said the strikes were conducted in the area of Bandar Abbas, where Iran's main naval base is located.

The U.S. sank two Islamic Revolutionary Guard Corps ships attempting to lay mines in the Strait of Hormuz and Iran launched surface-to-air missiles at U.S. planes, prompting the U.S. attacks on missile launchers near Bandar Abbas, officials said.