Dhaka – The members of the armed forces have begin search at in the rubble of a packaging plant set alight by an explosion near the Bangladeshi capital Dhaka, officials said on Monday.

The army was called in for the rescue operation after the firefighters doused the blaze at the factory of Tampaco Foils Ltd that produces packets for tobacco, chocolate and other consumer products, said firefighting officer Akhteruzzaman.

The four-storey factory building, located 20 kilometers north of the capital, collapsed hours after the fire broke out early Saturday.

Rescuers on early Monday pulled out two more bodies from the rubbles brining the death toll to 31, he said adding that the fire at the packaging plant was put out completely late on Sunday night.

Television footages show the rescuers, also from Fire Service and Civil Defence and police department, use heavy cranes and other equipments to pull the rubbles and remove the slabs of the collapsed building.

At least 24 people killed and 50 others wounded on the day factory was caught in fire after huge explosion. One of the survivors died in a hospital while the rescuers pulled bodies of six persons from the wreckage on the following days.

In the latest developments, the rescuers retrieved two bodies on Monday morning. But their identities could not be known.

An investigation has been launched into the cause of the explosion. Officials initially blamed a faulty boiler but investigators are also looking into the possibility of a gas leakage.

More than 50 people who suffer multiple injuries are undergoing treatment at different hospitals following the accident.

The district administration listed 11 factory workers as still missing after the accident, according to officials.

The Tampaco Foils factory produces packaging for tobacco and other consumer products, with British American Tobacco and food giant Nestle among its clients.

Nestle said Sunday it was “shocked and saddened” by the deaths and injuries in the fire. The Swiss firm said its thoughts were with those affected by the tragedy.

Fatalities in Bangladeshi factories – which mostly produce clothing, packaging and textiles – are common due to a lax implementation of regulations.

A fire at Tazreen Fashion factory in late 2012 killed at least 112 workers.

More than 1,100 people were killed and 2,500 injured after the collapse of the Rana Plaza building which housed five garment factories in 2013.