The death toll from the blazes Tuesday evening in a large clothing factory in Karachi and a shoe factory in Lahore was expected to rise, The New York Times reported. At least 289 people were killed in Karachi, where the factory employed 1,500 people, and 25 in Lahore.
At the factory in Karachi many were trapped by locked doors and barred windows, fire officials said.
"Workers, who were in the basement, died due to suffocation," Ehtisham-ud-din Salim, the chief fire officer of Karachi, said. "All exit ways were closed."
He described the factory as "packed like a box with little room left for ventilation" and said toxic smoke killed many of the victims.
City official Karachi Roshan Ali Skeik told Geo TV News the factory was in such bad shape the building could collapse at any time.
Rauf Siddiqi, industries and commerce minister for Sindh province, said the owner was being investigated for negligence.
"We have ordered an inquiry into how the fire erupted and why proper emergency exits were not provided at the factory so that the workers could escape," Siddiqi said.
In Lahore, officials said at least 25 people, including the factory owner and his son, died after fire broke out in shoe sole-making factory, Indo-Asian News Service reported.
Forty-five people were at the facility when the fire broke out.
Officials said the factory's location on a narrow street made it difficult for firefighters to reach the building to fight the fire and remove the injured and dead, IANS said.
Rescuers had to break through the walls and windows to enter the building, officials said. The Times reported officials said the building was designed to look like a residential structure and was being used illegally for manufacturing.
The fire is believed to have started when a generator exploded, igniting chemicals and plastic materials, one official said.
"The door caught fire, and there was no way to come out," Muhammad Amjad, who works in a nearby factory, told the Times. "It was just like an inferno all of sudden. Many people from the neighborhood tried to break the back wall of the building to help those trapped inside to get out."
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