As the sun came up over Lahore, soldiers and police scrabbled through the debris of the building, which came crashing down less than two weeks after a 7.5 magnitude earthquake rocked the region.
The factory may have suffered structural damage in the October 26 quake, which killed almost 400 people across Pakistan and Afghanistan, Punjab chief minister Shahbaz Sharif said.
“I have heard about the earthquake affecting the building, but according to labourers the owner continued to build an extension,” he told reporters.
Abdul Razzaq, a rescue official at the scene, told AFP they were racing against time to get to people still believed alive.
“The operation will take time and our aim is to reach the areas of the rubble where we are still hearing voices of crying and help,” he said.
Mohammad Usman, the top administration official in Lahore, who was coordinating the response to the disaster, said Wednesday 70 people had been pulled out alive, including 51 taken to hospital.
The army said it was deploying specialist search teams and engineers to help the rescue effort.
The collapse occurred at the four-storey Rajput Polyester polythene bag factory in the Sundar industrial estate, around 45 kilometres (30 miles) southwest of Lahore’s city centre.
Jam Sajjad Hussain, a spokesman for the rescue services, said 100 people were still trapped several hours after the roof collapsed, while ambulances were taking the injured to hospital.
“All our rescue workers are on site but it is such a big incident that we have called rescue workers from other nearby districts,” he added.
– Poor safety record –
Three cranes, a bulldozer and more than 40 emergency rescue vehicles were working at the site, a rescue official said.
But provincial spokesman Zaeem Qadri told reporters that progress was slow because the factory was at the end of a narrow lane making it difficult for excavators to reach the site.
He added that an emergency has been declared at all local hospitals.
Chief doctor Zia Ullah of Jinnah Hospital, where some injured have been taken, said most of the victims were young workers, with many suffering head injuries and fractured limbs.
Pakistan has a poor safety record in the construction and maintenance of buildings.
At least 24 people died last year when a mosque collapsed in the same city, while more than 200 people lost their lives, mostly due to collapsed roofs, following torrential rain and flooding in 2014.
In 2012, at least 255 workers were killed when a fire tore through a clothing factory in Karachi, one of the deadliest industrial accidents in Pakistani history.
A judicial probe into the blaze was damning, pointing to a lack of emergency exits, poor safety training of workers, the packing in of machinery and the failure of government inspectors to spot any of these faults.
A murder case was registered against the factory owners, but it has never come to trial.