Jalandhar, Apr 16 (IANS): At least one person was killed and several workers feared trapped under debris after a four-storeyed blanket factory building collapsed here, police said Monday.

At least 55 people had been rescued by teams of the local fire brigade and Punjab police personnel after rescue operations began early Monday, police said in Jalandhar, 150 km from state capital Chandigarh.

Police said the building of the blanket manufacturing factory, Sheetal Fabrics, located in the city's Focal Point area, collapsed following a blast in the factory's boiler around midnight Sunday.

Sources said up to 100 workers were inside the factory when the building collapsed. The huge factory building was completely flattened.

Two bodies were trapped under the collapsed building, said an official of the National Disaster Response Force (NDRF) team, which reached here Monday morning.

The factory is owned by prominent Jalandhar-based industrialist Sheetal Vij, who refused to comment on the mishap.

Most of those rescued had injuries and were admitted to hospitals here for treatment, said Deputy Commissioner Priyank Bharti.

"We heard a big blast and then around us started to fall. We were lucky that we ran out before the whole building came crashing down," a migrant labourer working at the factory told media at the site.

Rescue teams of the NDRF, district administration, Punjab police Army and Central Reserve Police Force (CRPF) were trying to get out the remaining trapped workers.

The deputy commissioner said that the exact number of trapped workers was being ascertained. He said the exact cause of the collapse was yet to be found.

"Information from the factory owners revealed that there were 60-70 workers inside the factory when the building collapsed," Bharti said.

Rescue and relief operations were continuing despite early morning rain in the city.