Temperatures fell to minus 8 degrees Celsius amid heavy snowfall at the mountain resort town of Murree overnight, killing at least 22 people who were stuck in their vehicles.

The military has been mobilised to clear roads and rescue people still trapped. (Source: Twitter)
The military has been mobilised to clear roads and rescue people still trapped. (Source: Twitter) ()

At least 22 people have died in an enormous traffic jam caused by tens of thousands of visitors thronging a Pakistani hill town to see unusually heavy snowfall.

Police reported that at least six people had frozen to death in their cars, while it was not immediately clear if others had died from asphyxiation after inhaling fumes in the snowdrift.

Interior Minister Sheikh Rashid said the military had mobilised to clear roads and rescue thousands still trapped near Murree, around 70 kilometres (45 miles) northeast of the capital, Islamabad.

Sheikh Rashid said residents had sheltered people trapped in the town and provided blankets and food to those they could reach on the outskirts.

Rescue 1122, Pakistan's emergency service, released a list naming 21 people it said had been confirmed dead.

It included a policeman, his wife and their six children.

Over 100,000 cars had entered the scenic town of Murree in the past few days to see the unusually heavy snowfalls, causing an enormous traffic jam on roads leading in and out, a police spokesman said. 

Murree, about 70 kilometres (45 miles) northeast of Islamabad, has long been popular for day trips from the capital.

PM orders inquiry

The Punjab province chief minister's office said Murree had been declared a "disaster area" and urged people to stay away.

Prime Minister Imran Khan said he was shocked and upset at the tragedy.

"Unprecedented snowfall & rush of ppl proceeding without checking weather conditions caught district admin unprepared," he tweeted.

"Have ordered inquiry & putting in place strong regulation to ensure prevention of such tragedies."

Authorities said schools and government buildings had taken in those who could make it to the town from the clogged roads.

Authorities warned last weekend that too many vehicles were trying to enter Murree, but that failed to discourage hordes of daytrippers from the capital.

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'Cold or carbon monoxide'?

Videos shared on social media showed entire families, including children, lying dead in their snow-covered vehicles.

“Were the deaths caused by cold or carbon monoxide (CO) poisoning?," Dr. Faheem Yonus, chief of infectious diseases at the University of Maryland UCH, said in a tweet. 

"CO is odorless, lethal if an idling car is buried in snow, the blocked exhaust (silencer) can quickly kill the passengers as they breath CO."

Officials have given no word on the causes of the deaths. 

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Source: TRTWorld and agencies