Police have seized 14 firearms and a cross bow from people who have failed to uphold firearm storage requirements in Melbourne’s inner north-west.

As part of an operation targeting breaches of firearm storage, police from the North West Metro region knocked on the doors of 62 houses in northern and western suburbs to check licensed owners were storing their guns correctly.

Detective Superintendent Alan Byrnes said that nearly one in five gun owners were found breaking the storage conditions, which he said was ‘‘unacceptable’’.

‘‘We found one owner’s firearm unsecured and hidden in a duct, while another owner could not account for missing firearms,’’ he said.

Requirements include making sure that guns are locked away in a secure cabinet, and a steel cabinet if the gun is high-powered; bolting the firearm to its storage structure if it weighs less than 150 kg; and fitting the premises with an intruder alarm system if more than 15 guns are stored on the property.