Dhaka, March 17 -- A deadly explosion that ripped through a residential flat in Chattogram's Halishahar, killing six members of a family, has not been caused by a gas leak, according to investigators.

The findings emerged in a report by a four-member probe committee formed by Karnaphuli Gas Distribution Company Limited (KGDCL) following the Feb 23 pre-dawn blast at Halima Manzil, a six-storey building in Block H.

The explosion occurred in a third-floor flat and was followed by a fire.

Nine members of a family suffered severe burn injuries in the incident.

Six later died while undergoing treatment at the National Institute of Burn and Plastic Surgery in Dhaka.

Initial assessments by different agencies had suggested a gas leak as the l...