They were already in a holiday mood as it was their last working day before the weeklong Eid vacation beginning today.

But it turned out to be the last day in the lives of at least 24 people, mostly workers, as they were killed in a massive fire triggered by explosions at a packaging factory in Tongi of Gazipur yesterday.

Around 50 suffered injuries when flames tore through Tampaco Foils Limited's factory in BSCIC industrial area of Tongi, close to the capital, at the start of a new shift.

"The workers were preparing to go to their village homes as the factory is going into Eid holidays tomorrow [today]. But everything got devastated," said Shahidul Islam, a staff in the engineering section of the factory.

Of the dead, 12 have been identified as Abdul Hannan, Jahangir Alam, Shankar Sarker, Rafiqul Islam, Shubhash Chandra Shaha, Anisur Rahman, Idris Ali, Rezwan Ahmed, Ismail Hossain, Anwar Hossain, Al Mamun, and Rashed Mia.

Lt Col Musharaf Hossain, director (training, development & planning) of Fire Service and Civil Defence Department, said the fire originated from boiler explosion.

However, MA Mannan, chief inspector of boilers, claimed that the cause of the fire was not boiler explosion.

The raging blaze reduced the factory to ruins as parts of the upper floors of the four-storey building caved in.

Black plumes of smoke from the building spiralled upward, engulfing the area in the initial hours of the incident, the biggest industrial disaster since 2013 when the Rana Plaza building collapsed.

Police said about 100 people were in the factory at the time of the incident; the workers of the morning shift were taking charge from night-shift colleagues. The plant runs in three shifts round the clock -- eight hours each.

The fire, which began at 6:05am, could not be extinguished till 2:00am today.

Fire officials said the explosion was huge and the fire triggered by the blast spread quickly because flammable chemicals and oil drums were stored at the factory.

About 150 firefighters of 25 units and around 50 volunteers worked since morning to douse the blaze, but they had to struggle from outside of the building as they could not enter it.

"We could not rescue anyone alive from the building yet,” Lt Col Musharaf Hossain told The Daily Star at 5:00pm. “Locals rescued some people alive before we reached the spot."

He said the factory was risky since it was housed in a 40-year-old building. "We have not been able to enter the building as there are chemical containers in the factory," he added.

The company manufactures paper backed foils, plug wrap paper, cigarette paper, filter tipping paper and printed, metalised and laminated films for different local industrial units as well as multinational organisations.

The explosion at the factory was so strong that it caused large chunks of debris to fly in all directions, said locals. Even some windowpanes at a few nearby buildings were broken off due to the impact of the blast, they added.

"The explosion shook the entire area," said Riyad Ahmmed, a factory official who lives nearby.

Mariam Akter Lima, who lives in a tin-roofed house to the north of the factory building, said, "We woke up to the loud sound of a blast. Within seconds, we heard some heavy objects falling on our tin roof."

She and other family members stormed out of their house and ran to safety.

"Then I saw plumes of black smokes billowing out and flames in some places. Screams were all around. It was devastating," said Mariam, a class-X student.

Rup Chan, a truck driver, said he heard the sound of explosions twice.

"The first blast caused a wall of the factory to collapse and fall on a rickshaw with two female passengers. I rushed to rescue them but then I heard another explosion," he said.

Witnesses and neighbours said 30 to 40 people were rescued alive from the factory by the locals at the initial stage of the fire. Many of the workers were trapped inside the building and begging for help.

"Waving their hands through the windows of the factory, the workers were crying for help but those who were outside could not go near the building due to huge flames," said Gul Chan, a housewife of a nearby tin-shed house.

Selina Begum, another neighbour, said she saw a person fall onto an adjacent tin-roofed building after squeezing out of the small window of the building.

"It was around 7:00am. We rushed there and found him unconscious. We took him to hospital," she said.

But, she added, the locals could not save those trapped inside because of the extreme heat of the inferno.

Some survivors said they heard the sound of gas leaking before the explosion.

"As I finished my night-shift and was preparing to come out of the factory, I heard the sound of gas leaking at the pipeline inside," said Kamrul Hasan, a worker who suffered injuries.

Nineteen bodies were taken to Dhaka Medical College Hospital. Five were either brought dead or they died of their injuries at the hospital, according to DMCH sources.

Some relatives gathered near the factory with photos of workers not found among the dead or the injured. 

Meanwhile, President Abdul Hamid and Prime Minister Sheikh Hasina expressed their condolences to the families of the people who died in the fire incident.

INFERNO UNTAMED

The factory blaze also engulfed an adjoining five-storey building. Both the buildings are owned by Tampaco and situated on one compound.

There was no access to the buildings for an effective fire fighting as the compound with only one entry is surrounded by industrial and residential structures, said Jahirul Amin, deputy director of fire service, around 1:30am today.

The buildings are very long in shape and both have deposits of chemicals making fire fighting very difficult, he said.

A Buet expert team that visited the site in the afternoon said that the five-storey building too might collapse and warned the firefighters against attempting to enter it.  

They were doing defensive fire fighting to ensure that the fire did not engulf any other adjoining buildings and structures, said Jahirul. 

Around 50 families, including children, women and elderly persons who lived in tin-shed structures along the factory's boundary walls on both sides were seen stranded on nearby Station Road, since they had to leave their houses because of heat and falling debris of the collapsed factory building.

“A neighbour's son died after a concrete slab from the four-storey building fell on him, and my house was smashed under another chunk,” said an elderly Jahura Begum, who was among the stranded along with son, daughter-in-law and two grand children.

Autopsies on the bodies of the victims completed at DMC morgue around 1:00am today and process to hand them over to families has begun after that.       

PROBE COMMITTEES, COMPENSATION

Three separate probe committees were formed to investigate the incident.

The Fire Service and Civil Defence Department formed a five-member probe body with its Deputy Director Badiuzzaman as the head. It will submit report in seven working days.

The BSCIC formed a three-member committee with engineer Md Shafiqul Alam, its regional director of Dhaka, as its head. The team has to submit its report within the next seven days, said the BSCIC in a statement yesterday.

The team has to find out the cause of the fire, determine responsibility and make recommendations.

Meanwhile, Gazipur district administration also formed a five-member probe committee led by Executive Magistrate Rehanul Islam. It will submit its report in 15 working days.

The Department of Inspection for Factories and Establishments (DIFE) also formed a three-member body, said its Inspector General Syed Ahmed. It will find out the cause of the incident, he said.

Home Minister Asaduzzaman Khan visited the site around 4:30pm and said the government would take action against the owners of the factory and will file cases.

The probe teams will look into whether the boiler was inspected in time, said the minister.

Families of the deceased will get Tk 2 lakh each in compensation, said State Minister for Labour and Employment Mujibul Haque Chunnu while visiting the spot.

The ministry will also ensure proper medical treatment for the injured.

Established in 1978, the factory has around 350 workers working in three shifts, said workers and locals.

Some of the big names in the consumer market in Bangladesh are clients of Tampaco Foils, according to the company's website.

Tampaco Chairman Syed Mokbul Hussain was president of Bangladesh Flexible Packaging Industries Association from 1998 to 2002.