People gather around a car damaged after a tree fell during a rainfall in Lahore. AFP

The storms hit four districts of Khyber Pakhtunkhwa province late on Saturday, with five siblings aged between two and 11 among the dead.

"At least 12 people were buried alive after the roofs and walls of their houses collapsed," Taimur Ali Khan, a spokesman for the provincial disaster management authority, told AFP. More than 140 people were injured and more than 200 livestock died, he said.

Authorities have declared an emergency in all four districts.

The affected districts of KP province are Bannu, Lakki Marwat and Karak, senior rescue officer Khateer Ahmed said, uprooting trees and knocking down electrical transmission towers. Officials were working to provide emergency relief to the injured, Ahmed said.

Last year, monsoon rains and flooding devastated Pakistan, killing more than 1,700 people, affecting around 33 million people and displacing nearly 8 million.

To mitigate the effects of natural disasters, the government in its national budget draft presented on Friday allocated $1.3 billion for climate resilience.

An injured victim of rain storm is treated at a hospital in Bannu. AP

Pakistani Prime Minister Shahbaz Sharif expressed grief over the loss of life loss from the storm and directed authorities to pick up the pace of the relief operation.

Meanwhile, a cyclone is making its way across the Arabian Sea towards the coastlines of Pakistan and India, expected to make landfall at the end of the week.

The "severe and intense” cyclone with wind speeds of 150 kilometres per hour was on a course toward the country’s south, Pakistan's disaster management agency said.

Pakistani authorities said they would begin evacuating between 8,000 and 9,000 families from along the coastline of Sindh province, including in the mega port city of Karachi, home to around 20 million people. The army will be deployed from Monday to assist.

People bathe along the Seaview Beach in Karachi on Sunday. AFP

The cyclone could bring winds, storm surges and urban flooding from Tuesday evening as it approaches, the disaster management agency said Sunday.

"Fishermen are advised not to venture into the open sea until the (weather) system is over by June 17," the agency said.

Prime Minister Shahbaz also ordered officials to put in place emergency measures in advance of the approaching Cyclone Biparjoy in the Arabia Sea.

Motorcyclists ride a motorbike along a street during a rainfall in Lahore. AFP

Scientists say climate change is making seasonal rains heavier and more unpredictable.

Pakistan, which has the world's fifth largest population, is responsible for only 0.8 percent of global greenhouse gas emissions but is one of the most vulnerable nations to extreme weather caused by global warming.

Last summer, unprecedented monsoon rains put a third of the country under water, damaging two million homes and killing more than 1,700 people.

Agencies