Dozens of people were killed Thursday when a bus carrying children came under attack in Yemen’s northwestern Saada province, according to the International Committee of the Red Cross (ICRC).

“Following an attack this morning on a bus carrying children in Saada’s northern Dahyan Market district, an ICRC field hospital received dozens of dead and injured,” the ICRC’s Yemen office said in a tweet.

It did not provide any details about the incident, but nevertheless held Yemen’s Houthi rebel group responsible for the attack.

“Under international humanitarian law, civilians must be protected during conflict,” the ICRC said.

Yemen has remained wracked by violence since 2014, when Shia Houthi rebels overran much of the country, including capital Sanaa.

The conflict escalated in 2015 when Saudi Arabia and its Sunni-Arab allies launched a massive air campaign in Yemen aimed at rolling back Houthi gains.

Houthi spokesmen, for their part, blamed the Saudi-led coalition for Thursday’s deadly attack.

“On Thursday morning, Saudi air power carried out a heinous massacre targeting a school bus in the city of Dahyan in Saada,” group spokesman Mohamed Abdel-Salam said in a statement.

The attack, he said, had left “dozens” of people -- including a number of school students -- dead or injured.

The Saudi-led coalition, for its part, has yet to comment on the incident.

This article has been adapted from its original source.