At least 10 people, including a patient, were killed when an oxygen cylinder exploded inside a parked ambulance at a government-run medical facility in southern Pakistan, police and hospital officials said Thursday.
The explosion occurred overnight in Tharparkar district of Sindh province, District Police Chief Arif Aziz said.
The victims included medical facility staff, patients and their relatives, he said.
Local police official Khalil Abro said patients were being transferred to another hospital when the blast occurred.
Images circulating on social media and television showed flames engulfing the ambulance, with one of its doors open. Another image showed the vehicle's charred frame outside a building as people gathered nearby.
Pakistani President Asif Ali Zardari expressed grief over the deaths and called for a swift and transparent investigation to establish the cause of the explosion, according to a statement from his office.
He also urged authorities to strengthen safety measures to prevent similar incidents, extended condolences to the victims' families and wished those injured a speedy recovery.
In August, a fire caused by an exploding air conditioner killed 14 newborns in a nursery at the Pakistan Institute of Medical Sciences in Islamabad. The only baby rescued from the nursery died weeks later, raising the death toll to 15.