WASHINGTON — A U.S. Navy destroyer was fired on again with a cruise missile Wednesday off the coast of Yemen, according to the Defense Department's spokesman.

The USS Mason detected the missile at 6 a.m. ET. The ship fired countermeasures to thwart the missile, which landed harmlessly in the water, according to Peter Cook, the Pentagon's press secretary.

It’s unclear if the Navy’s response protected the ship, or if the missile simply missed. No sailors were hurt, and the USS Mason was undamaged.

The attack occurred south of Al Hudaydah, an area controlled by Houthi rebels who are backed by Iran. A similar attack failed on Sunday.

The Mason is deployed to the Red Sea as part of the Eisenhower Carrier Strike Group. The Mason is supporting security operations in the region, which has been the site of confrontations with pirates and Iranian vessels suspected of carrying weapons to the Houthis.

"Those who threaten our forces should know that U.S. commanders retain the right to defend their ships, and we will respond to this threat at the appropriate time and in the appropriate manner," Cook said.

The Navy won't be deterred from patrolling the Red Sea, Adm. John Richardson, the Chief of Naval Operations, said in a statement.

"We are trained and ready to defend ourselves and to respond quickly and decisively," Richardson said. "The team in USS Mason demonstrated initiative and toughness as they defended themselves and others against these unfounded attacks over the weekend and again today."

Yemen has been consumed by a civil war between the Houthi rebels, backed by Iran, and Yemen’s government, which has international recognition.

Saudi Arabia has led a bombing campaign against the Houthi rebels, but that effort has been implicated in several incidents of civilian deaths.

The U.S. military also conducts airstrikes in Yemen. Two weeks ago, the Pentagon announced that it had killed two al-Qaeda operatives there.