The Andhra Pradesh State Forensic Science Laboratory (APSFSL) here has detected both burnt and unburnt crackers in a quantity sufficient enough to cause high intensity fire on board the ill-fated Tamil Nadu Express.
The train which caught fire near Nellore resulted in the death of about 35 passengers.
Crackers and materials that went into the making of fireworks were found from the remnants of the burnt S 11 coach, the APSFSL Director O. Narasimha Murthy said.
The fire originated in the bay of seat numbers 53 to 58 but what initiated it was not known. The intensity of the fire was more in bays 6 (for seats 53 to 58), 7 and 8. The burning of crackers accompanied by wind owing to movement of train propagated the fire, Mr. Murthy added.
On the chemicals used in the fireworks, he said they included potassium chlorate, potassium chloride, sulphur, aluminium and magnesium. There were different varieties of crackers of various brands and these included hydrogen bombs, which were sound producing and flower pots.