Eight people were killed and 15 others injured when a boiler of an ice factory exploded in Pakistan"s southern port city of Karachi on Tuesday, local reports said.

The factory"s building collapsed to the ground following the explosion, trapping several laborers inside which are being recovered and shifted to the hospital, the reports added.

The explosion also damaged three adjacent factories and several people working in them were also injured, said the report.

The factory"s administrator said that over 50 people were working inside the factory when the incident happened and rescue teams are trying to recover the trapped laborers.

Police said that heavy machinery is being used to recover the trapped people from the debris.