A hospital in northern Yemen was hit by airstrikes on Monday, with a local medical official saying that 15 people had been killed.
The de facto authorities in northern Yemen, dominated by the Houthi rebel movement, blamed the attack on a Saudi-led coalition against the rebels, which has repeatedly pounded the region.
International medical charity Doctors without Borders (MSF) confirmed that a hospital it supported in Abs, Hajjah province, was hit by an airstrike at 15:45 local time (1245 GMT).
"Medical teams are assisting the wounded & toll is still unknown," MSF's Yemeni branch wrote on Twitter. It did not assign responsibility for the attack.
Hajjah's provincial health director, Ayman Madhkour, said that 15 people were killed and more than 25 injured in the attack, which he said was carried out by coalition aircraft.
Eye witnesses told dpa that the strike hit the hospital's emergency department. The victims were all civilians, including many women and children, Madhkour said.
Northern Yemen has been hit by frequent airstrikes by the Saudi-led coalition which supports Yemeni President Abd Rabu Mansour Hadi against the mainly Shiite Houthis, who control the capital Sana'a.
On Saturday 10 children were killed in an attack on a school in neighbouring Saada province, according to MSF. Houthi officials blamed the coalition for that attack.
The conflict, ongoing since early 2014, has intensified since peace talks between Hadi's government and the rebels were suspended on August 6.
UN Secretary General Ban Ki-moon last September called for a halt to the coalition's air campaign, saying it was responsible for most of the conflict's civilian casualties.
Shelling by the Houthis and allied forces on residential areas, especially in the central city of Taiz, has also resulted in considerable civilian casualties.
In June, Ban controversially removed the Saudi-led coalition from the annex of a UN report flagging entities that have killed and maimed children in conflicts.
He subsequently said that the decision had been taken under "undue pressure," including threats from member states to pull funding from various UN agencies in response to the listing.
Earlier on Monday, the coalition announced that it would permit the UN and humanitarian organizations to operate flights into Sana'a airport, whose closure it ordered after the suspension of the peace talks.
An alliance of 12 aid groups had Sunday said the closure of the airport put millions of lives at risk. They called for it to be reopened to commercial as well as aid flights in order to facilitate the arrival of vital supplies and free movement of civilians.
"The closure effectively seals Yemen off from the rest of the world at a time when half the population is malnourished and hospitals urgently require more medicine and medical supplies," Syma Jamil of the Norwegian Refugee Council said.
Yemen, one of the poorest countries in the Arab world, has been devastated by the conflict, which pits the Houthis and their ally, deposed president Ali Abdullah Saleh, against Hadi and a wide range of other forces including local tribes, Sunni Islamists, southern Yemeni secessionists and jihadis.
By Amal al-Yarisi and Pol O Gradaigh
