A fire in the newborn room of the gynecology ward at the Pakistan Institute of Medical Sciences hospital in Islamabad killed at least 15 newborns, hospital authorities said on Wednesday. Sixteen newborns were in the nursery when the fire broke out, and only one was rescued alive.

Rescue agency sources said the fire began inside the nursery at about 6:45 a.m. local time. Preliminary information indicated that it spread after an air-conditioner compressor exploded. District administration said rescue teams responded immediately, with six fire service vehicles and four ambulances joining the operation.

According to district administration information, 14 children were completely burned in the fire on the third floor of the hospital's MCH ward. Rescue workers said the blaze had been brought under control and cooling work was under way after it was fully extinguished. The district administration has formed an investigation committee led by the additional deputy commissioner to determine the actual cause and examine how the incident occurred.