The death toll from heavy monsoon rains that have triggered landslides and flash floods across northern Pakistan has risen to at least 321 people, according to the disaster authority.

Most of the deaths, 307, were recorded in the mountainous Khyber Pakhtunkhwa province in northwestern Pakistan, with another five killed in the northern region of Gilgit-Baltistan and nine in Pakistan-administered Kashmir, it said.

Earlier, the authority had said 225 people died in the flood-hit Buner district of Khyber Pakhtunkhwa province.

Most were killed in flash floods and collapsing houses, with the dead including 15 women and 13 children. At least 23 others were injured.

The government said a helicopter on a rescue mission in the flood-hit province crashed due to the bad weather, killing the five crew members.

Reporting from Islamabad, Al Jazeera’s Kamal Hyder said the helicopter was a military aircraft.

“This was a Pakistani military helicopter that was involved in a rescue operation. Helicopters are being used to help people in areas that are hard to access,” he said.

Hundreds evacuated

Dozens of people were injured as the deluge destroyed homes in villages in Buner, where authorities declared a state of emergency.

Rescuers evacuated 1,300 stranded tourists from the mountainous Mansehra district, which was hit by landslides on Thursday. Dozens of people were reported missing in these areas, according to local officials.

The meteorological department has issued a heavy rain alert for Pakistan’s northwest for the next few hours, urging people to take “precautionary measures”.

The provincial government has declared the severely affected mountainous districts of Buner, Bajaur, Swat, Shangla, Mansehra and Battagram disaster-hit areas.

Floods in Indian-administered Kashmir

The annual monsoon season brings South Asia 70 to 80 percent of its annual rainfall, which is vital for agriculture and food security but also brings destruction.

Landslides and flash floods are common during the season, which usually begins in June and eases by the end of September.

In Indian-administered Kashmir, rescuers continued to search for survivors under boulders and debris on Friday, a day after sudden floods triggered by heavy rains killed at least 60 people and left 200 missing.

Gushing mudslides and floodwaters inundated the village of Chisoti on Thursday, washing away pilgrims who had gathered for lunch before trekking up a hill to a popular religious site in the second such disaster in the Himalayas in a little more than a week.

The Himalayas are prone to floods and landslides, but some scientists said the intensity and frequency of these events are increasing due to climate change.