The all-clear has been given after police cordoned off two streets in Hamilton when workmen discovered a piece of an unexploded device under a house being readied for removal.
Police were called to a property in Willoughby Street shortly after 10.30am on Friday.
The device was found under a drain pipe and the Defence Force's explosive disposal team from Auckland called in.
Police say the device was a mortar shell and there was no risk of it exploding.
