CAIRO－The death toll from a Saudi-led coalition airstrike that hit a prison run by Yemen's Houthi rebels has climbed to at least 82, the Houthi group and an aid group said on Saturday.

Internet access in the Arab world's poorest country remained largely down as the coalition continued airstrikes on the rebel-held capital, Sanaa, and elsewhere.

The airstrike in northern Saada Province on Friday was part of an air and ground offensive that marked an escalation in Yemen's years of civil war. Saada is one of the main strongholds of the Iran-backed Houthis who have been fighting the Yemeni government forces backed by the Saudi-led coalition for years.

Ahmed Mahat, head of a Doctors Without Borders mission in Yemen, told The Associated Press his group counted at least 82 dead and more than 265 wounded in the airstrike.

Rescuers were still searching for survivors and bodies in the rubble of the prison site in Saada, on the border with Saudi Arabia, the Houthis' media office said.

The number could increase as the rescuers continue their search for bodies at the bombing site, the Houthi health authority said.

"The airstrike destroyed the prison building, and there is insufficient equipment to pull the victims from under the rubble," an official of Saada's local authority said.

The Houthi-affiliated Al-Masirah television network reported that the coalition launched more than 59 air raids across the country.

The intensified bombardment included the country's Red Sea port city of Hodeidah, destroying a telecommunications center and causing a nationwide collapse of internet connectivity.

The airstrikes came after the Houthis claimed responsibility for attacking the United Arab Emirates, an active member of the Saudi-led coalition, with ballistic missiles and explosive-laden drones.

Hundreds of Houthis staged a large protest in the capital of Sanaa against the deadly airstrikes carried out by the Saudi-led coalition.

On the other side, the Saudi-led coalition said it would continue "the process of responding to the ballistic and drones threat launched by the Houthis toward Saudi Arabia".

Yearslong war

Yemen has been mired in a civil war since late 2014, when the Houthi militia seized control of several northern provinces and forced the internationally recognized government of president Abd-Rabbu Mansour Hadi out of Sanaa.

The conflict has since become a regional proxy war in which tens of thousands of civilians and fighters have died. The war has also created the world's worst humanitarian crisis, leaving millions suffering from food and medical care shortages and pushing the country to the brink of famine.

Xinhua - Agencies