The Armed Offenders Squad was called out following reports of a man with a firearm threatening another man in Westport this afternoon.
Sergeant Andrew Lyes says the alleged offender was arrested without incident soon after police arrived at around 4pm.
No one was injured during the incident and the weapon was recovered from the scene, he said.
A 25-year-old man was arrested and remanded in custody to appear in court on Monday on firearms charges.
No one else is being sought in relation to the incident, Mr Lyes said.