Four people returning from a Hindu pilgrimage have died while traveling in a non-air-conditioned coach on an Indian train during a summer heat wave.

Temperatures during the day Tuesday had soared to 48 Celsius (118 Fahrenheit).

Railway official Manoj Kumar says the four, who were between 69 and 81 years old, were part of a group returning to the southern state of Kerala after visiting the holy city of Varanasi in northern India.

Kumar said the four fell sick in their coach and the doctors who attended to them at Jhansi station found them dead. They were sent for autopsies.

Traveling in air-conditioned coaches is too expensive for many poorer Indians.

Schools and colleges were closed due to the heat wave, and people advised to stay indoors during daytime.