A young man is being spoken to by police after he allegedly put a pipe bomb into a rural Waihi letterbox last night.
The 18-year-old was ``playing around with fireworks'' when he made the explosive, Inspector Steve Kose of northern police communications said.
The bomb was discovered by the ownerof the Waihi property after he spotted a vehicle pull up to the letterbox about 10pm and took note of the vehicle's registration number.
"Then he opened the letterbox and he saw a 15cm pipe in there,'' Mr Kose said.
The owner was lucky the bomb did not explode, he said.