The Colombo North Crime Investigation Division officers arrested a suspect with an automatic weapon at the Ramanadan Apartment complex in the Offshore Police division on Friday night.
Police have also recovered a magazine with four 9mm ammos in his possession.
The suspect is a 53-year-old resident of Jampettah Street, Colombo 13. Preliminary investigations revealed that the suspect had been arrested earlier by the Maradana Police for possessing 16 kilograms of Kerala cannabis. The suspect was to be produced before the Aluthkade No. 6 Magistrate.
Offshore Police are investigating.