Torrential rains in northeast India have sparked heavy flooding killing at least four people, government disaster officials said Wednesday.

More than a million people have been impacted by floods, according to government figures.

Monsoon rains cause widespread destruction every year, but experts say climate change is shifting weather patterns and increasing the number of extreme weather events.

Disaster authorities in the northeastern state of Assam said 38 people have been killed since mid-May when heavy rains battered the state, triggering floods and landslides.

India’s weather department has issued alerts for Assam and neighboring states warning of the risk of more flash floods.