Dozens of people have been killed when a Saudi-UAE-led military coalition battling the Houthi rebel movement bombed a prison in western Yemen, according to the rebels.

Yusuf al-Hadri, a spokesman for the Houthis' ministry of health, said at least 60 people were killed in Sunday's air raids which hit a complex used as a detention centre north of Dhamar city

Fifty people were wounded, he told the rebel-run Al Masirah TV, adding that 185 prisoners of war were being held overall at the Dhamar Community College.

Nazem Saleh was among those held at the facility. "We were sleeping and around midnight, there were maybe three, or four, or six strikes," he told The Associated Press news agency.

"They were targeting the jail, I really don't know the strike numbers ... We were 100 persons on the ground level and around 150 on the upper level," he said while on a stretcher in a local hospital.

Earlier, Houthi spokesman Mohammed Abdulsalam had said in a Twitter post that the toll was 50 people killed and more than 100 wounded.

In a statement carried on Saudi state television, the coalition said it had launched air raids on Houthi military targets in Dhamar and destroyed a site storing drones and missiles.

The Western-backed coalition, which has come under intense criticism by rights groups for air attacks that have killed civilians, said it had taken measures to protect civilians in Dhamar and the assault complied with international law.