A teenager has been rescued 50 hours after getting trapped under the rubble of a four-storey factory which collapsed in eastern Pakistan.

At least 26 people were killed and 103 injured in the collapse in Lahore.

Identified only as Shahid, the teenager was among the unspecified number of missing, a government official said. He appeared to be in stable condition.

Rescuers have been carefully removing debris in hopes of retrieving more survivors.

The rescue came hours after authorities said hopes were starting to fade for finding more survivors.

Jam Sajjad Hussain, a spokesman for the Punjab emergency service, said the 400 rescuers saved the lives of 103 workers since Wednesday, when the building suddenly caved in.

The cause of the collapse is yet to be determined.

It happened just over a week after a magnitude-7.5 earthquake hit Pakistan, killing 273 people and damaging nearly 75,000 homes.