A gang of armed robbers allegedly travelled by boat along the Hooghly to reach the site of an under-construction riverbank residential complex in north Calcutta early on Thursday morning.
A gunfight followed as the project’s security guards shot back at the gang when they opened fire.
Police have arrested three men and detained six minors in connection with the case.
All of them were from a slum under the jurisdiction of North Port police station. The police said they used a dinghy to reach the project site.
A manager for Oswal Orchard Amritya, the under-construction riverside residency on Rustamji Parsi Road in Cossipore, has lodged a police complaint.
The police said Debasish Nath, the manager, alleged that the group reached the site through the river route and entered the compound after breaking open the perimeter fencing.
“The intruders looted construction materials, including aluminium panels, concrete pipes, steel and iron rods and electrical conduit pipes,” the police said.
The police said the gang opened fire at the staff cabin to create panic.
Two armed private security guards posted at the site allegedly returned fire.
The offenders then fled through the waterway with the stolen materials, an officer said at the Kolkata Police headquarters in Lalbazar.
A special investigation team (SIT), comprising officers from different police stations under the North Division, has been formed to probe into the daring robbery.
“Through sustained investigation and source development, the SIT traced the gang and conducted raids. Nine persons were apprehended in connection with the crime, including three men and six juveniles,” police said.
Investigators said the police had recovered a portion of the booty.
The police said further investigation was being carried out to ascertain the modus operandi of the gang and to recover the firearms allegedly used during the robbery.