At least 43 people were killed in Pakistan, most in a remote village that did not receive an evacuation warning before flash floods hit, washing away most of the settlement, officials said.
The heavy monsoon rains began late on Saturday and were concentrated mainly in the north-western province of Khyber Pakhtunkhwa, which has been badly affected by flooding in recent years that some scientists have linked to climate change.
The worst-hit district was Chitral, on the country's north-west border with Afghanistan, where the flood waters killed 41 people in the village of Ursoon near the Afghan border, which is home to some 100 families, district mayor Maghfirat Shah said.
Eighty-two homes in the village were affected by the waters, a rescue services statement said, with some of them swept away, along with a mosque and an army post.
"Sixteen of the dead were offering prayers in the mosque when it was swept away by the flood," said Latifur Rehman, a spokesman for the provincial disaster management authority.
At least eight of the victims were soldiers, and another eight bodies were swept over the border into Afghanistan, senior local official Osama Waraich said.
Mr Rehman said a military-led rescue and relief operation had begun, with helicopters being used to reach the affected people and provide them with tents, food and medical aid.
Separately, two Chinese engineers were killed and five Pakistani workers injured when the heavy rains caused the roof of a construction site to collapse at Tarbela Dam, also in Khyber Pakhtunkhwa province, Mr Rehman said.
Prime Minister Nawaz Sharif's office issued a statement expressing his grief.