According to news agency PTI, the Southern Railway said that an “illegal gas cylinder” on board led to the fire. The passengers of the “private party coach” had arrived from Lucknow in Uttar Pradesh.

The fire broke out at 5:15 amand the fire service personnel who arrived at the spot half an hour later put down the blaze by 7:15 am, a Southern Railway release said.

“This is a private party coach that was attached at Nagercoil Junction yesterday (Aug 25) by train no. 16730 (Punalur-Madurai Exp). The party coach was detached and kept at Madurai Stabling line. The passengers in the private party coach have….smuggled gas cylinder and this has caused the fire,” the release said.

The party coach had started the journey from Lucknow on August 17, scheduled to return to Chennai on Sunday and return to Lucknow from there, it added.

“While the coach was stabled/parked, some members of the party in the private party coach were using the illegally smuggled cooking gas cylinder unauthorisedly for preparing tea/snacks, which caused the fire in the stabled/parked coach. Most of the passengers could get out of the coach on noticing fire. Some passengers had already got down at platform also before detachment of coach,” it added.

An amount of Rs 10 lakh was being paid to each of the family of those who died, it said.

Southern Railway also announced two helpline numbers for information related to the fire incident and causalities– 9360552608, 8015681915.