Hopes of finding more than 180 missing people alive waned as rescue workers searched through mud and debris after landslides set off by torrential rains killed at least 194 people in southern India.

The rescue work was challenging in a forested, hilly area while more rain fell on Thursday, said PM Manoj, a spokesman for Kerala state’s top elected official. Nearly 40 bodies were found downstream after being swept some 30km (20 miles) down the Chaliyar river from the area in Wayanad district where the main landslides occurred. Body parts were also recovered.

Torrents of mud and water swept through tea estates and villages in hilly areas in the district early on Tuesday. They flattened houses and destroyed bridges, and rescuers had to pull out people stuck under mud and debris.

Manoj said 187 people were unaccounted for as of Thursday. In addition to the dead and missing, 186 people were injured. Local media reported most of the victims were tea estate workers.

More than 5,500 people have been rescued, the government said, with some 1,100 rescue personnel, helicopters and heavy equipment involved in the operations.

The army was constructing a temporary bridge after the main bridge in one of the worst-affected areas was swept away.

Kerala, one of India’s most popular tourist destinations, is prone to heavy rains, flooding and landslides. The India Meteorological Department said Wayanad district had received up to 28cm (11 inches) of rain on Monday and Tuesday.