At least 14 infants were killed in a fire at a state-run hospital in Pakistan’s capital Islamabad on Wednesday, the prime minister said, with the health minister attributing the tragedy to a blast in the nursery ward.

The blaze started around 7 a.m. at the Pakistan Institute of Medical Sciences, on the third floor of the hospital’s mother and child health ward, said broadcaster Geo TV, which put the death toll at 15.

“The fire erupted after a blast in (an) air conditioner”, Health Minister Mustafa Kamal told Geo TV, adding that ample oxygen in the ward helped it spread.

The incident is among the deadliest hospital fires in recent years in the country, where government healthcare is subsidised but facilities are under-resourced and overburdened. Watchdogs have frequently criticised state-run facilities as mismanaged.

Television footage showed a gutted, blackened ward with scattered equipment and smoke still rising. There were 16 newborns in the ward when the fire broke out, one of whom was rescued, Geo reported.

The ward was later cordoned off, a Reuters witness said.

Footage showed grief-stricken women sitting on the ground outside the hospital. One of them was Javeria, who lost her newborn to the fire.

“It was a gynaecology ward … there was no doctor, no nurse”, she said, adding that the bodies of the children were taken away “in boxes” and the women did not get to see them.

“It is not God’s will… I don’t accept it”, she said.

Kamal denied accusations that there were no staff or doctors present at the time of the fire.

Prime Minister Shehbaz Sharif suspended the health secretary over the incident, his office said, hours after he ordered an investigation.

The building that housed the ward “had no fire security, no proper exits. All doors were closed, only one door was (open) for us to visit our children”, said Mudasir, who also lost his child. Javeria and Mudasir both gave only their first names.

PIMS, where former Prime Minister Imran Khan was briefly taken for a medical check last week, is centrally located in Islamabad and is one of the main public hospitals of the city of around 1.1 million people.