Police are dealing with reports of three suspected explosive devices throughout the Tauranga area.
Senior Sergeant Mark Holmes said the Auckland bomb disposal squad were on their way to look at an old box reading "charge spotting mine" which was found in Mangatapu.
No one had been evacuated as the bomb squad did not believe it was of particular concern.
Mr Holmes said police were also investigating reports of a torpedo-shaped object found in a Greerton bus depot this afternoon. He said officers there were also liaising with the bomb squad.
The third explosive was found while police were executing a search warrant in Hairini.
Mr Holmes said it was a Thunderflash, an explosive used by police in training exercises. Tauranga officers were able to deal with it without the aid of a specialist unit.