The fire broke out in a nursery for newborn babies at the Pakistan Institute of Medical Sciences (PIMS), sources told CNN.

According to rescue officials cited by the US news network, the blaze was apparently triggered by an explosion involving an air-conditioning compressor inside the nursery.

Hospital authorities reportedly managed to rescue one baby from the ward. Several other children were left in critical condition, raising concerns that the death toll could increase.

Islamabad Chief Commissioner Sohail Ashraf said on X that rescue teams, police personnel and officials from the AC Industrial Area immediately reached the site and brought the fire under control.

“We shall keep you updated regarding casualty or any other news,” Ashraf said.

However, hospital authorities did not immediately confirm the reported death toll.

PIMS spokesperson Dr Aneeza Jalil told Dawn that 15 babies had been admitted to the ward.

“Some of the babies may have been discharged during the night, so the exact number [of casualties] cannot be shared right now,” she said.

The hospital is one of the major healthcare facilities in Islamabad and is located in a key part of the Pakistani capital.