Kolkata police on Saturday, 18 July detained one person in connection with a bomb explosion at a house in the Dakshin Narayanpur area of Rajarhat, in the northern outskirts of Kolkata. The blast, which occurred the previous night, left one person seriously injured and caused extensive structural damage to the building. The prime suspect, identified as Md Shamim alias Salim, a resident of the Kamarhati area of North 24 Parganas district, remained at large as of Saturday.

How the Explosion Unfolded

According to police, two individuals had rented a room in the house through a broker approximately two to three days before the incident. The tenants told the house owner they would be out during the day and return only at night. On the night of the explosion, one of them was seen on CCTV cameras entering the premises carrying a white bag. He left the bag inside the room and exited. Roughly 10 minutes later, a powerful blast rocked the building.

The intensity of the explosion was significant enough to rupture walls and blow out doors. Two rooms sustained extensive damage. A tenant in the adjacent room was seriously injured and has since been admitted to hospital, according to police.

Evidence at the Scene

After the blast, investigators found a large number of bomb strings scattered at the site, according to police. Authorities are now probing whether explosives had been stored in the room prior to the night of the incident. Other residents of the building, who described themselves as terrified, told investigators the bomb was likely transported inside the white bag.

Officers from the West Bengal Fire Services Department, the Special Task Force (STF) of the state police, and the bomb squad reached the site on Saturday to sanitise the affected structure. A team from the National Investigation Agency (NIA) is reportedly likely to visit the site for further inquiry.

Detention and Ongoing Investigation

Police detained one individual on Saturday in connection with the case and commenced questioning. The prime suspect, Md Shamim alias Salim, remains on the run. Investigators are working to establish the full chain of events, including how the explosives entered the building and whether additional individuals were involved.

What Comes Next

The possible involvement of the NIA signals that central agencies may treat the incident as potentially linked to a wider network rather than an isolated event. With bomb strings recovered and CCTV footage secured, investigators are expected to move quickly to identify and apprehend the remaining suspect. The safety of other residents in the building — and the broader Rajarhat locality — remains a concern as the sanitisation of the site continues.