Fourteen newborn babies died after a fire swept through the maternity ward of the Pakistan Institute of Medical Sciences (PIMS) in Islamabad, prompting an investigation and the suspension of Pakistan’s federal health secretary.

The fire broke out on Wednesday morning in an air conditioning unit on the third floor of the hospital’s mother and child unit. A hospital spokesperson told the BBC that the fire was quickly intensified by oxygen connections in the ward.

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Fifteen newborns were inside the affected ward when the fire started. Only one survived, according to the hospital.

Seven other babies, 10 mothers and two men were rescued from the unit, Pakistan’s Minister of State for Interior Talal Chaudhry said.