New Delhi, June 14 -- A massive fire that broke out in a five-storey residential building in southeast Delhi's Tughlakabad area earlier this week, killing three people and injuring eight others, was a deliberate act of arson carried out as part of a personal vendetta, Delhi Police said on Sunday.

The fire erupted in the TKD Extension area of Tughlakabad on June 12 and was initially believed to have been caused by negligence. However, police later found evidence suggesting the fire had been intentionally set.

Police registered a case under relevant sections of the Bharatiya Nyaya Sanhita (BNS) after reviewing CCTV footage that showed a woman entering the building shortly before the fire broke out.

During the investigation, police arrest...