A specially fortified hospital in northern Syria has been evacuated after it was bombarded with bombs, as the UN declared the Syrian health system to be "on the verge of collapse".
The 'cave hospital' in rural Hama, near Aleppo, was built underground to ensure the safety of its patients.
When the hospital opened in 2015, one aid organisation said "nothing will happen" even if the hospital is repeatedly shelled.
"Maybe it will shake the place, but the place would endure," Mohammad Yasser Tabbaa said.
However, medical staff suspect missiles specially designed to penetrate bunkers were used on the hospital in two waves on Sunday, causing it to partially collapse.
The UOSSM, a union of medical care and relief organisations in Syria, said the first wave of air strikes hit at 3pm, with another later in the evening.
The blasts caused "extensive damage" to the emergency room and other parts of the hospital, with pieces of brick and concrete falling from the ceiling. Those inside sustained minor injuries.
Dr Abdallah D, the hospital's director and head of the Hama Healthcare Directorate, described the blasts as "complete destruction".
"It is suspected that the hospital was targeted by 'bunker buster' missiles as the hospital was well fortified in a cave and impervious to previous attacks," he said.
"The bomb caused complete destruction of the emergency department and major destruction throughout the hospital."
The hospital is officially named after Dr Hasan Al-Araj, a cardiologist and its former director, who was killed by an air-to-surface missile in April.
All doctors, nurses and equipment were moved from the hospital after it was hit.
The hospital, which performs around 150 surgeries per month and deals with at least 40 intensive care cases, will be rebuilt.
The attack comes in the days after several hospitals in Aleppo were targeted, destroying one and putting three others out of service.
In a statement on Sunday, Stephen O'Brien from the UN Office for the Coordination of Humanitarian Affairs said he was "deeply alarmed" hospitals, mainly in eastern Aleppo, had been targeted.
"Medical facilities are being hit one by one. I have received reports of attacks on at least three hospitals including a paediatric hospital providing services to thousands of sick and injured children," he said.
"The health system is on the verge of total collapse with patients being turned away and no medicines available to treat even the most common ailments.
"This conflict must end."