India, Dec. 7 -- As investigations begin into the devastating fire at a nightclub in Goa's Arpora that killed at least 25, key question about how an allegedly illegal venue with safety violations continued to operate and what exactly triggered the blaze remain unanswered.

The fire at the Birch by Romeo Lane nightclub in Arpora broke out after midnight on Sunday, according to police, cited in a PTI news agency report. Track latest in Goa nightclub fire probe here

The blaze killed at least 25 people, including four tourists and 14 staff members of the nightclub.

Goa police chief Alok Kumar told PTI that the fire occurred due to a cylinder blast. But multiple witnesses dispute this version. Some said the fire began on the first floor, whe...