Five older travellers aboard the Kerala Express from Coimbatore to Agra in June died from heat stroke, according to autopsies.
They were part of a 68-strong group all from Tamil Nadu, part of a 10-day trip to Varanasi to visit pilgrim centres. The dead were travelling in compartments which lacked air conditioning.
Temperatures in India have been around 48 degrees centigrade.
Photo credit: Barry Pousman