At least three people including an infant were killed after a four-storey building collapsed in Sindh's Sukkur district on Thursday evening, officials said.

Twelve people were pulled out of the debris in an injured condition. They were shifted to Sukkur's Civil Hospital for first aid, where a one-year-old baby and two women succumbed to their injuries.

Officials said several people are still feared to be trapped under the rubble. Rescuers, including Pakistan Army and Rangers personnel, are using heavy machinery to lift the debris from the site.

Two out of the nine injured being treated at the Sukkur hospital were referred to Larkana due to their critical condition.

The building, located on Sukkur's busy Station Road, was constructed above a few shops and housed four families.

Rescuers at the scene initially faced difficulties after the building collapse caused a power blackout in the area.

Commissioner Sukkur Shafiq Ahmed Mahesar, who was supervising rescue efforts at the collapse site, confirmed the casualties while talking to media.

He revealed that more than 20 members of four brothers' families were living in the four-storey building. He said more people were feared to be trapped under the rubble and efforts were underway to rescue them.

Mahesar said the building could have collapsed either because substandard material was used in its construction or because it was not built according to the approved maps. However, the actual cause will be investigated, he added.

Sindh Chief Minister Murad Ali Shah took notice of the incident and sought a report from the Sukkur commissioner.