SAADA: More than 100 people were killed or wounded in an air strike on a prison and at least three children died in a separate bombardment as Yemen’s long-running conflict suffered a dramatic escalation of violence on Friday.

The Houthi rebels released gruesome video footage showing bodies in the rubble and mangled corpses from the prison attack, which levelled buildings at the jail in their northern heartland of Saada.

Further south in the port town of Hodeida, the children died when air strikes by the Saudi-led coalition hit a telecommunications facility as they played nearby, Save the Children said. Yemen also suffered a country-wide internet blackout.

“The children were reportedly playing on a nearby football field when missiles struck,” Save the Children said.

The attacks come five days after the Houthis took the seven-year war into a new phase by claiming a drone-and-missile attack on Abu Dhabi that killed three people.

The United Arab Emirates, part of the Saudi-led coalition fighting the rebels, threatened reprisals.

Aid workers said hospitals were overwhelmed in Saada after the prison attack, with one receiving 200 wounded, according to Doctors Without Borders.

Basheer Omar, spokesperson for the International Committee for the Red Cross in Yemen, told AFP: “There are more than 100 killed and injured... the numbers are going up.”

Ahmed Mahat, Doctors Without Borders’ head of mission in Yemen, said: “There are many bodies still at the scene of the air strike, many missing people. It is impossible to know how many people have been killed. It seems to have been a horrific act of violence.”

The United Nations Security Council is due to meet at 1500 GMT on Friday in an emergency session on the Houthi attacks against the UAE, at the request of the Gulf state, which has occupied one of the non-permanent seats on the council since January 1.

The UAE is part of the Saudi-led coalition that has been fighting the rebels since 2015, in an intractable conflict that has displaced millions of Yemenis and left them on the brink of famine.

The coalition claimed the attack in Hodeida, a lifeline port for the shattered country, but did not say it had carried out any strikes on Saada.