Kalutara Crime Investigation Division (CID) arrested a man with a revolver manufactured in Sri Lanka in Horana, yesterday.
The thirty-three-year-old suspect is a resident in Aththidiya.
The suspect is due to be produced before the Horana Magistrate court today.
Further investigations revealed that the suspect is a member of the underworld and is a heroin dealer.
He is said to have been convicted of several robberies at previous occasions.
Horana Police is investigating.