BEIRUT, Lebanon — Airstrikes hit four hospitals in rebel-held northern Syria on Monday, including child and maternity facilities, international aid officials and witnesses reported. The United Nations said at least 50 people were killed, including children.
It was unclear who was responsible for the attacks, which came days before international powers have called for a “cessation of hostilities” in the five-year Syria war. Russian and Syrian aircraft operate in the areas where the hospitals were struck.
Two of the four hospitals were supported by Unicef. Anthony Lake, Unicef’s executive director, said in a statement, “Apart from compelling considerations of diplomacy and obligations under international humanitarian law, let us remember that these victims are children.”
Farhan Haq, a spokesman for the United Nations in New York, told reporters at midday that the death toll was 50. It remains unclear how many of the casualties were children.
Doctors Without Borders, the international medical charity, said the airstrikes destroyed one of the hospitals it supports, killing at least seven, wounding eight and leaving an unknown number of patients buried in rubble.
The hospital, in the town of Maarat al-Noaman, in insurgent-held Idlib Province, was hit by four missiles in two sets of attacks within a few minutes of each other, the charity said, citing reports by hospital staff members.
The charity added that about 15 other buildings had been struck in residential areas nearby.
It was the second time in a week that a hospital working with the charity was hit. The charity said an affiliated hospital was bombed in Dara’a Province in southern Syria on Feb. 9.
“This appears to be a deliberate attack on a health structure, and we condemn this attack in the strongest possible terms,” Massimiliano Rebaudengo, the Doctors Without Borders head of mission, said about Monday’s strike on its affiliate. Deliberate attacks on medical facilities are forbidden under international law.
The hospital had 30 beds, 54 staff members, two operating rooms, clinics and an emergency room, and its destruction leaves 40,000 people without medical care, the charity said.
Antigovernment activists and residents said warplanes also attacked three other hospitals on Monday. Three people were killed and six wounded in one, the National Hospital, which is also in Maarat al-Noaman. And in Azaz, a major prize in the fierce battles unfolding in Aleppo Province, two hospitals were hit, at least one of them by what residents and the Turkish government said was a ballistic missile.
A school housing displaced people was also damaged, residents said.
Azaz is one of the most complex theaters of the war in Syria, with combatants from many sides clashing, sometimes with putative allies. Turkey has fired artillery into Syria, saying it is aiming at Kurdish-led forces that have taken territory from Turkish-backed fighters.
Russian officials have said their country’s airstrikes do not target civilians and have not killed any.
Russia’s Foreign Ministry declared that Turkey, by shelling the Kurds as they battled insurgents, was providing “direct support for international terrorism.” It also insisted that the American-led coalition fighting the Islamic State was responsible for the hospital bombing in Maarat al-Noaman, but United States military officials said there were no coalition strikes in the area. The United States and allied insurgent groups say that Russia has bombed indiscriminately.
Syrian antigovernment monitoring groups say that Russian strikes have been the single largest cause of deaths in the war this year, and that they have killed hundreds of civilians, hitting schools, medical facilities and residential areas.
The strikes came amid days of escalation along the Syria-Turkey border, despite the United States and Russia having agreed on Thursday in Munich to work for a cease-fire, said to be starting by the end of this week.
Doctors Without Borders has found its hospitals increasingly coming under fire in conflict zones. American airstrikes killed 42 people at an affiliated hospital in Kunduz, Afghanistan, last year. The charity’s hospitals have also been hit in a Saudi air campaign in Yemen.
Physicians for Human Rights, an organization that has been tracking attacks on health care workers and infrastructure amid the Syrian conflict, says it has documented 336 attacks on medical sites that have killed 697 staff members, the vast majority carried out by the Syrian government and its allies.