Police are investigating after a teenager suffered burns to his hands when a "deactivated" mortar shell he bought on the internet blew up in his hands.
Luke Stillman, 16, from Walgrave, Northamptonshire, bought the apparently decommissioned Spanish 81mm mortar from a website advertising specialist auction material.
The boy was dismantling the round at his family home when it exploded, injuring his fingers and damaging the desk on which it had been placed, police said.
Luke needed hospital treatment for his injuries.
The website, Specialist Auctions, said the vendor had now been banned from trading.
They said: "We are very strict that the ordnance sold is inert."
Detective Sergeant Andy Rogers, of Northamptonshire Police, said: "This incident could potentially have resulted in Luke sustaining a much more serious injury. As it was, his fingers were burned and the table he was sitting at was damaged.
"Anyone of any description should exercise the greatest care when doing so. Messing around with any ordnance is potentially very dangerous.
"If you discover ordnance of any description, steer clear and contact the police immediately.
"We need to know how this mortar round was still live and available for purchase in this country and, to that end, we are investigating to see whether any criminal offences have been committed under the Firearms Act."
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