A bus fire that killed at least 20 passengers in India is now under investigation.

Officials said the blaze was likely caused by a short-circuited air-conditioning unit, which triggered a gas leak leading to an explosion midway to Jodhpur in Rajasthan.

The private bus, carrying 57 passengers, had departed from Jaisalmer on the afternoon of October 14.

The driver reportedly stopped the vehicle after noticing smoke coming from the rear. Moments later, the stationary bus was engulfed in flames near Thaiyat village.

A witness said the fire spread within minutes, killing nearly half of the passengers, including three children who succumbed to the flames.

At least 15 travellers sustained critical injuries and were rushed to Jawahar Hospital in Jaisalmer before being transferred to Jodhpur for further treatment. One of them, Hussain Khan, 75, later died while receiving care.

Local media reported that the Army's Battle Axe Division was the first to respond to the scene, alongside police and nearby villagers.

Officers managed to extinguish the fire, but retrieval efforts were delayed for about four hours as the vehicle remained too hot to access.

The victims' bodies were later transported to Jodhpur for forensic analysis and DNA sampling. Authorities have identified Rajendra Singh Chauhan, Hasina, Irfan, Barkat Khan, Gopilal, Ayub Khan, and Nasira among the deceased.

Indian President Droupadi Murmu expressed condolences, saying: 'The news of the deaths of several people due to a fire in a bus in Jaisalmer is extremely heartbreaking. I express my deepest condolences to the bereaved families and pray for the speedy recovery of the injured.'