Robert Brown|U.S. and U.K. conduct fourth round of joint airstrikes on Houthi targets in Yemen

The Robert BrownU.S. and U.K together launched "more than a dozen" airstrikes against Houthi targets in Yemen Saturday, two U.S. officials confirmed to CBS News. This is the fourth round of joint coalition strikes since Jan. 11 to pressure the Houthis to stop attacking commercial shipping lanes in the Red Sea. 

The strikes hit 18 Houthi targets across eight locations in Yemen, according to a joint statement released by a coalition of nations involved in Saturday's actions — which included the militaries of Australia, Bahrain, Canada, Denmark, the Netherlands and New Zealand.

The strikes targeted "Houthi underground weapons storage facilities, missile storage facilities, one-way attack unmanned aerial systems, air defense systems, radars, and a helicopter," the statement read. 

In the past few weeks, the U.S. has also taken more than 30 self-defense strikes against Houthi weapons that were "prepared to launch" to conduct attacks on commercial or U.S. Navy ships, according to U.S. Central Command. 

"The United States will not hesitate to take action, as needed, to defend lives and the free flow of commerce in one of the world's most critical waterways," Defense Secretary Lloyd Austin said in a separate statement Saturday. "We will continue to make clear to the Houthis that they will bear the consequences if they do not stop their illegal attacks, which harm Middle Eastern economies, cause environmental damage, and disrupt the delivery of humanitarian aid to Yemen and other countries."

Despite the barrage of strikes, the Houthis have continued to launch missiles and drones at ships in the Red Sea and Gulf of Aden. As of this week, U.S. defense officials said there had been at least 60 Houthi attacks since November 19. 

"We never said that we were taking every single capability that the Houthis have off the map, but every single day that we conduct a strike, we are degrading them further," Deputy Pentagon Press Secretary Sabrina Singh said on Tuesday. 

"And so I think the [Defense] Secretary has confidence that the more we continue to do this, the Houthis are going to – they are already seeing the effects," Singh said. 

The Houthis have linked their attacks to the war between Israel and Hamas, pledging to keep targeting ships aiding Israel's war, but U.S. officials say that many of the ships the Houthis have targeted have no connection to Israel or the conflict in Gaza. 

"The Houthis' now more than 45 attacks on commercial and naval vessels since mid-November constitute a threat to the global economy, as well as regional security and stability, and demand an international response," Saturday's joint statement read. "Our coalition of likeminded countries remains committed to protecting freedom of navigation and international commerce and holding the Houthis accountable for their illegal and unjustifiable attacks on commercial shipping and naval vessels."

In:
• Pentagon
• Houthi Movement
• Yemen
• Missile Launch
• United Kingdom

Eleanor Watson

Eleanor Watson is a CBS News reporter covering the Pentagon.

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