The number of people known to have died in India’s heatwave that has swept the country since mid-April has reached around 800.
In some areas such as Bhopal in the central state of Madhya Pradesh temperatures have reached nearly 50 degrees Celsius.
The authorities have advised people to stay indoors but the reality for many of the poor is that they have to work outside.
In the worst-affected southern states of Telangana and Andhra Pradesh hospitals are overflowing with people suffering from sun stroke and dehydration.
In Andhra Pradesh, more than 550 have died from the heat.
Emergency health centres have been set up and doctors’ leave cancelled.
“This year, the summer is very severe. Due to that, our people are getting dehydrated and they’re facing so much of feeling like fainting, and they’re feeling very sick,” said Sister Angelo, in charge at a Mother Teresa home in the port city of Visakhapatnam.
In the capital New Delhi roads and tourist sites were relatively empty on Tuesday afternoon as temperatures soared to 45 degrees.
Aid organisations have been asked to open up drinking stations.
Forecasters have issued a “red alert” through till the end of Wednesday in several states.