Houthi media outlet Al Masirah showed images of people in the rubble after Friday’s strike at a detention centre in the northern Yemeni city of Sa’ada. The Red Cross said it had delivered emergency medical supplies to two hospitals with a “very high” number of casualties.

“According to my colleagues in Saada, there are still many bodies at the site of the airstrike, and many people are missing,” said Ahmad Mahat, MSF’s Yemen mission leader. “It is impossible to know how many there are. People were killed. It seemed like a horrific act of violence.”

Mahat said a MSF-supported hospital in Saada had been overwhelmed by the influx of wounded and could not take in more. Two other hospitals in the city also suffered heavy casualties, according to MSF.

Multiple rescue workers told CNN that international aid groups have been working to gather details about the strike because of internet outages.

The Saudi-led coalition did not comment on the strike at the telecommunications building or the detention center, but said on Friday it had attacked the port of Hodeidah, destroying “one of the [Houthis’] A den of pirates and organised crime. “

The coalition also said it attacked “military targets” in the capital Sana’a on Friday, claiming it “in response to the threat of a hostile attack,” the Saudi state-owned SPA said.

The ICRC said: “The ICRC is deeply concerned about the intensification of hostilities in recent days, including attacks on cities in Yemen, Saudi Arabia and the United Arab Emirates, and regrets the loss of life caused by this escalation. ,” said Friday.