Heavy rains were hampering a search for residents feared buried under piles of debris as the death toll from landslides in India's tea-growing region of Darjeeling reached 38, police said Thursday.

The rains have triggered fresh landslides in the Mirik area where rescue teams were struggling to find those buried in the mud and debris that barrelled down slopes on Tuesday night into their homes.

Darjeeling district magistrate Anurag Srivastava said rescue workers were using their bare hands and basic tools to clear debris, with blocked roads stopping heavy equipment from reaching the site.

"Fresh landslides washed away a road near Mirik making it impossible to transport heavy equipment to remove boulders and debris," Srivastava, who is overseeing the rescue operation in Mirik, told AFP.

"The rescue team are using their hands to search for people and clear the debris, but further rain is making it difficult."

The original landslides also struck homes built on slopes in Kalimpong and Darjeeling in West Bengal state, leaving a trail of destruction in the scenic region.

"The victims were killed in their sleep. No one got the opportunity to escape," Srivastava said.

Darjeeling district police superintendent Amit P Javalgi said the death toll had reached 38 after the discovery of more bodies with "at least 11 people still missing".

Some 2,000 people have been evacuated from the sites of landslides which have also cut bridges and triggered power cuts.

"Rescuers are using heavy lifting equipment for the first time to clear roads leading to the site of the disaster," Javalgi said.

The weather bureau in Kolkata has forecast more heavy rain for the coming days.

Floods and landslides hit South Asia every year during the monsoon season.