KARACHI: The death toll from heavy snow in a famous hill station near Pakistan's capital Islamabad rose to 23, as rescue workers backed by army troops struggled overnight to scrap snow off the roads, Anadolu Agency (AA) quoted officials on Sunday.

Massive snowfall over the past three days buried Murree, a scenic hill station located some 65 kilometres (40 miles) off Islamabad, and its adjoining valleys under a thick layer of snow, blocking roads, knocking off power, and sending panicked tourists scurrying for shelter.

Thousands of vehicles packed with tourists were trapped due to the snowstorm in the valley and the adjacent areas over the past three days.

At least 23 people, including eight of a family, lost their lives mainly because of cold and lack of oxygen as thousands of vehicles were trapped on different roads in and around Murree over the past two days, forcing the government to call the army in.

Major Gen Akhtar Nawaz, head of the National Disaster Management Authority, a state-run agency that coordinates between different relief and rescue agencies, told reporters that rescuers are still working to clear a key road, where most of the deaths occurred.

Remaining roads and arteries, he said, have been cleared for traffic, and all the stranded tourists have been shifted to hotels and army camps.

However, he added, "many" abandoned vehicles are still trapped under the snow, causing trouble for the rescuers who are struggling to clear the main road that connects the picturesque valley with rest of the country.

Some 600 to 700 vehicles were rescued overnight, according to Murree police. Footage aired on local broadcaster Geo News showed army troops clearing the roads with heavy machinery, and rescuers sprinkling salt on the roads in an attempt to melt a thick layer of snow.

Meanwhile, Prime Minister Imran Khan has ordered an inquiry into the incident, focusing as to why tourists were not stopped from visiting the hill station despite a clear warning of extraordinary snowfall by the meteorological department.

Pakistan's north and northwestern valleys are experiencing heavy snowfall this year, a clear indication of the climate change impacts.

Pakistan is among the 10 countries, which are expected to be badly hit by the climate change.

Hundreds of thousands of people from across Pakistan travel to Murree and adjoining tourist destinations to enjoy snowfall in winters.

According to police, over 100,000 vehicles have entered Murree over the past one week.

-- BERNAMA