Saudi-led coalition air strikes on rebel-held security buildings in western Yemen have killed at least 60 people, many of them inmates buried under the rubble of their detention centre.

The strikes late Saturday came just hours after other coalition raids hit three residential buildings in the southwest of the country, killing 17 civilians.

Yemen’s President Abedrabbo Mansour Hadi on Saturday rejected a UN peace proposal aimed at ending his country’s 19-months conflict against the Shiite Huthi rebels and their allies.

Forces loyal to Hadi’s government have been locked since 2014 in deadly battles with the rebels, who seized the capital Sanaa late that year.

The conflict escalated in March 2015 when the Saudi-led coalition launched a military campaign to push back the rebels, after they advanced from the capital including towards the coastal province of Hodeidah.

In the latest deadly strikes in Hodeidah, which the rebels have controlled since late 2014, coalition warplanes hit a rebel-held security compound in the town of Zaidia.

“Sixty people in total were killed and dozens were wounded,” a health official said.

Most of the victims were anti-rebel detainees who were being held among 100 inmates in two cells at the detention centre, he said.

It remains unclear why the coalition would hit a detention centre holding anti-rebel inmates.

‘Lack of medical supplies’

AFP footage from the site showed the bloodied limbs and bodies of the victims covered in dust and buried under the rubble as sirens wailed nearby.

“We were about to go to sleep when an air strike targeted us,” said a wounded man at a hospital in the area.

“We ran away and a second air strike hit us again,” he said, as medics rushed around bringing in wounded victims covered in blood.

The rebel-controlled also gave a toll of 60 killed and 38 wounded, adding that “dead bodies are still being retrieved” from under the rubble.

Coalition warplanes hovering over the area “are hampering attempts to save the victims and retrieve bodies,” reported.

International aid groups have repeatedly voiced concern over the rising need for aid in Yemen, where malnutrition has increased in the past months.

“The number of victims could rise further due to the lack of medical supplies,” it said, quoting a medical source who blamed the coalition’s “blockade”.

A lack of ambulances “has made attempts to transfer critical cases to hospitals in the city of Hodeidah more difficult,” the source said.