An investigation is underway after a police officer accidentally left their loaded Glock pistol in a Parliament bathroom.
Police national manager of response and operations Superintendent Chris Scahill says the incident is "regrettable".
Supt Scahill says as soon as they were made aware the police-issue firearm was left in a bathroom on Thursday, staff recovered it from the occupant.
"We would like to thank them for their assistance.
"This was a regrettable incident that we are taking seriously, and we acknowledge the potential risk that this could have posed," Supt Scahill says.
Parliament was sitting on Thursday, though the Prime Minister was not in Wellington.