At least 30 people are dead or missing after flash floods hit southern India, reports said Saturday, with three buses washed away in one incident.

Rescue teams pulled out a dozen bodies after three buses were washed away in Andhra Pradesh state on Friday. At least 18 other people were still missing, media outlet The News Minute reported.

Analysts say unpredictable and extreme weather across South Asia is driven by climate change, exacerbated by damming, deforestation and excessive development.

Dozens have died since October in India after heavy rains triggered floods and landslides, and the country's Met office said more heavy rains were expected in several southern areas on Saturday.

At least 42 people were killed last month when heavy rains pummelled Kerala, and on Friday authorities in the state halted entry to Sabarimala, one of Hinduism's holiest shrines, due to heavy rains in the area.

Hundreds of devotees have been making the trek to Sabarimala since the shrine opened last week for the annual two-month-long pilgrimage season.

Rising water levels in the Pamba river, considered holy by the pilgrims, forced officials to stop devotees for a day, the Hindustan Times newspaper reported Saturday.