Members of the Portland police crime investigation unit executed a raid at a residential property Blackwood Court, in Portland's east, about 8am Wednesday.

An unsecured longarm and ammunition was seized.

A 47-year-old Portland man was arrested, interviewed and charged with firearm-related offences.

Detective Sergeant Michael Vaughan said firearm carelessness should not be taken lightly.

"Police take any offence in the Firearms Act very seriously, especially when firearms aren't secured in a safe manner and where accidental discharges can occur," he said.

"Firearm carelessness should not and is not taken lightly."

The accused man was bailed to appear in Portland Magistrates Court on March 30 next year.

Anyone with information about illegal or unsecured firearms is urged to contact Crime Stoppers.

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