The United States has again pounded at least one key target in Yemen, reportedly knocking out a vital radar system.

The latest strike follows dozens of US and British strikes on the Iran-backed group’s facilities 24 hours earlier.

Biden administration officials, speaking on the condition of anonymity, did not provide more details.

Radar infrastructure, used to find targets and guide drone attacks, has been a key target in the US military effort to halt Houthi attacks on Red Sea shipping.

The Houthi movement’s Al-Masirah television channel reported the US and Britain were targeting the Yemeni capital Sanaa with raids.

Intensifying concerns about a widening regional conflict, US and British warplanes, ships and submarines on Thursday launched missiles against targets across Yemen controlled by the group, which has cast its maritime campaign as support for Palestinians under siege by Israel in Hamas-ruled Gaza.

‘Outrageous behaviour’

Even as Houthi leaders swore retaliation, Biden warned earlier on Friday that he could order more strikes if attacks continue on merchant and military vessels in one of the world’s most economically vital waterways.

“We will make sure that we respond to the Houthis if they continue this outrageous behaviour,” Biden told reporters during a stop in Pennsylvania on Friday.

Witnesses confirmed explosions early on Friday, Yemen time, at military bases near airports in the capital Sanaa and Yemen’s third city Taiz, a naval base at Yemen’s main Red Sea port Hodeidah and military sites in the coastal Hajjah governorate.

White House spokesman John Kirby said the strikes had targeted the Houthis’ ability to store, launch and guide missiles or drones, which the group has used in recent months to threaten Red Sea shipping.

The Pentagon said the US-British assault reduced the Houthis’ capacity to launch fresh attacks. The US military said 60 targets in 28 sites were hit.

The Houthis, who have controlled most of Yemen for nearly a decade, said five fighters were killed in the initial attacks and vowed to continue their attacks on shipping.

Drone footage on the Houthis’ al-Masirah TV showed hundreds of thousands of people in Sanaa chanting slogans denouncing Israel and the United States.

“Your strikes on Yemen are terrorism,” said Mohammed Ali al-Houthi, a member of the Houthi Supreme Political Council.

“The United States is the Devil.”

Biden, whose administration removed the Houthis from a State Department list of “foreign terrorist organisations” in 2021, was asked by reporters if he felt the term “terrorist” described the movement now.

“I think they are,” he said.

Gaza’s spreading shockwaves

The Red Sea crisis is part of the violent regional spillover of Israel’s war with Iran-backed Hamas in the Palestinian enclave of Gaza.

Hamas militants rampaged through southern Israel on October 7, killing 1200 people and seizing 240 hostages. Israel has responded by laying waste large sections of Gaza in an effort to annihilate Hamas. According to Hamas, the attacks have killed more than 23,000 Palestinians.

The strikes follow months of raids by Houthi fighters, who have boarded ships they claimed were Israeli or heading for Israel. Many of the vessels had no known connection to Israel.

The US and some allies sent a naval task force in December, and recent days saw increasing escalation. On Tuesday, the United States and Britain shot down 21 missiles and drones.

However, not all major US allies chose to back the strikes inside Yemen.

The Netherlands, Australia, Canada and Bahrain provided logistical and intelligence support, while Germany, Denmark, New Zealand and South Korea signed a joint statement defending the attacks and warning of further action.

But Italy, Spain and France chose not to sign or participate, fearing a wider escalation.

A senior US official accused Tehran of providing the Yemeni group with military capabilities and intelligence to carry out their attacks.

-AAP