At least 56 people have been killed and dozens are feared trapped after heavy rains triggered massive landslides in the southern Indian state of Kerala.
The landslides struck hilly areas in Wayanad district in the early hours of Tuesday.
Rescue operations are under way, but are being hindered by heavy rains and the collapse of a crucial bridge.
"We will be able to assess the extent of the damage only after a few hours," state minister AK Saseendran told BBC Hindi.
India's army said it had sent more than 200 personnel to the area to assist security forces in search and rescue efforts.
Local hospitals are treating at least 70 injured people, and around 250 people have been rescued and shifted to rescue camps so far.
Apart from the 36 confirmed deaths in Wayanad, nine bodies have been found in the Chaliyar river, which flows into neighbouring Malappuram district.
Wayanad, a hilly district which is part of the Western Ghats mountain range, is prone to landslides during the monsoon season.
The landslides have hit several areas in the district, including Mundakkai, Attamala, Chooralmala and Kunhome.
Videos on social media showed muddy water gushing through unpaved streets and forested areas, washing away homes and leaving people and vehicles stranded.
A bridge connecting Chooralmala to Mundakkai and Attamala has collapsed, isolating the two places and making it difficult for rescue personnel to reach trapped families.
Rashid Padikkalparamban, a resident, told Reuters news agency that at least three landslides had hit the area around midnight, washing away the bridge.
State and national disaster relief teams are conducting rescue operations. Several locals too have been helping out.
Mr Saseendran also said the army and air force have been asked to airlift trapped families and to build a temporary bridge.
Raghavan C Arunamala, a local, described the horrifying scenes unfolding in the area.
“I saw a man trapped in the debris shouting for help. Firefighters and rescue workers have been trying to reach him for the last few hours," he said.
“We fear hundreds of people are trapped inside the villages," he added.
Wayanad district and neighbouring areas are on alert due to the forecast of heavy rains.
Schools and colleges have been closed in 10 of 14 districts.
In 2019, 17 people had died after a landslide hit Puthumala in Wayanad, around 10km from the areas currently affected.
Tuesday's tragedy came up in India's parliament with Vice-President Jagdeep Singh Dhankar - the chairman of the upper house - calling it a "very painful situation".
Prime Minister Narendra Modi posted on X (formerly Twitter) that he had spoken to Kerala Chief Minister Pinarayi Vijayan and assured the federal government's help in relief efforts.
Mr Modi also announced compensation of 200,000 rupees ($2,388; £1,857) to the victims' families and 50,000 rupees to the injured.
Credit: BBC