KOLKATA: A late-night rooftop gathering in south Kolkata turned deadly after armed assailants opened fire, killing one man and critically injuring another in what police suspect is a fallout of a dispute over gambling money.

The incident took place around 1 am on Thursday in the Baghajatin area, where three friends were on the terrace of a residential building. Six men allegedly stormed the rooftop and fired multiple rounds.

Rahul Dey, 30, was killed in the attack, while his friend Jeet Mukherjee, 35, sustained serious injuries. A third person present at the scene managed to escape by hiding.

Police said Mukherjee, a building material supplier and resident of the building, was likely the primary target. Investigators believe the shooting was linked to a dispute over control of satta (illegal gambling) operations in the Narendrapur-Sonarpur belt.

Within hours of the incident, four accused were arrested. According to Joint Commissioner of Police (Crime) Rupesh Kumar, the suspects are from areas including Narendrapur and Vidyasagar Colony, and preliminary findings point to a conflict over gambling proceeds.

An FIR has been registered based on Mukherjee’s statement, in which he identified two of the attackers. Police are still trying to trace the third individual who was present with the victims, as his role remains unclear.

Officers from Kolkata Police said forensic teams recovered evidence from the scene, including an empty cartridge, blood samples, mobile phones, and other items. Motorcycles believed to have been used by the assailants were also seized nearby.

Rahul was taken to hospital but was declared dead on arrival. Mukherjee is undergoing treatment.

Police sources added that Mukherjee has a criminal history and was allegedly involved in local disputes over gambling and building material syndicates.

Family members of the deceased have alleged foul play and demanded a thorough investigation. Further probe into the case is ongoing.