At least 10 people were killed after an oxygen cylinder inside a parked ambulance exploded at a government health facility in Pakistan's southern Sindh province.

According to police and hospital officials, the explosion occurred during the night in the Tharparkar district. The victims included healthcare workers, patients and their relatives, officials said.

District Police Officer Arif Aziz said those killed in the blast included employees of the health facility, patients and attendants.

Local police official Khalil Abro said the explosion occurred while patients were being transferred to another hospital.

Images shared on social media and television channels showed a vehicle engulfed in flames after the blast. Other footage showed the charred remains of the ambulance near people standing in front of a building.

Investigation launched into deadly blast

Pakistan President Asif Ali Zardari expressed sorrow over the deaths and called for a swift and transparent investigation to determine the cause of the explosion.

In a statement issued by the presidency, Zardari urged authorities to strengthen safety measures to prevent similar incidents in the future.

He extended condolences to the families of those who lost their lives and wished a speedy recovery to those injured in the blast.(ILKHA)