A U.S. warship operating off the coast of Yemen was targeted a second time Wednesday by what appeared to be Iranian-backed Houthi rebels in southern Yemen, raising the likelihood of a U.S. military response, defense officials said.

Officials said the USS Mason, a destroyer, wasn’t hit or damaged when two missiles were fired from a Houthi-controlled area known as al-Hudaydah. Iran backs the Houthi rebels in Yemen, who have been engaged in a bloody civil war that pits them against a Saudi Arabia-led coalition that is backed by the U.S.

It was the second such attempted attack since Sunday, when missiles fired from the same region missed the Mason.

Defense officials warned they are contemplating a military strike in response.

“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,” Pentagon Press Secretary Peter Cook said in a statement Wednesday.