Sean McDermott of Gisborne said he cleaned up a brown mass his dog dug up at about lunchtime Tuesday and called police upon discovering it was an unexploded grenade, Radio New Zealand reported.
McDermott said police inspected the device and confirmed it was a hand grenade. He said they sent for the army expert, who told him the grenade was too old to explode.
The homeowner said the expert told him it used to be common practice for soldiers to keep grenades as souvenirs. The expert said McDermott's home was the fourth he had visited for a grenade removal that day.