Indian authorities shut schools, evacuated hundreds of thousands of people and cancelled trains in parts of the country as rescue teams braced on Thursday for a tropical storm brewing in the Bay of Bengal.

Cyclone Dana is expected to hammer the low-lying regions of West Bengal and Odisha, home to around 150 million people, as a “severe cyclonic storm” late on Thursday or Friday morning, India’s weather bureau said. At least 1.1 million people on India’s eastern coast were fleeing to storm shelters inland, just hours before the storm’s arrival.