Landslides in India have stranded hundreds of trucks carrying fuel and essential items to the violence-hit state of Manipur, police said on Thursday, after heavy rains caused devastation that killed at least 84 people.

Torrential rains that officials blame on climate change, coupled with unabated construction over the past few years in the mountainous Himalayan region, have also led to frequent flash floods and landslides in neighbouring Pakistan and Nepal.

Rocks and mud engulfed part of a highway near Imphal, the capital of Manipur, following Wednesday’s rains, stranding 400 trucks, police said, adding that incessant rain was hampering efforts to clear the road.

The state is trying to restore peace after it was hit by deadly ethnic violence that began in May, killing at least 180 people and driving tens of thousands from their homes.

Hundreds of structures have also crumbled down the mountains this week in landslides in the northwestern state of Himachal Pradesh, killing at least 68 people with about 15 missing, disaster management official Praveen Bhardwaj said.

The state’s chief minister, Sukhvinder Singh Sukhu, told the Indian Express newspaper he blamed indiscriminate construction and improper structural design among the reasons for the destruction.

In the neighbouring state of Uttarakhand, at least 16 people died in landslides this week with 15 missing by Wednesday, government figures showed.

Heavy seasonal monsoon showers since June 1 have brought rains exceeding the normal by 45% and 18% respectively in Himachal Pradesh and Uttarakhand, weather officials say, following significant volumes last month.

At least 88 people died in rain-related incidents in Himachal Pradesh last month, with 74 dying since June in Uttarakhand in events triggered by natural disasters, official data shows.