THE Royal Navy performed a controlled explosion after a phosphorous shell was found on a beach in West Sussex.
Bomb disposal experts based at Horsea Island in Portsmouth were called to Littlehampton after a 13-year-old boy discovered the device on East Beach.
The youngster was said to be unwittingly playing with the explosive marine marker when it started giving off smoke at around 2pm on Monday afternoon.
Police set up a 650ft cordon around the beach to keep members of the public at a safe distance while the navy’s elite squad of bomb experts got to work.
The device was discovered to be a marine marker dating from the 1950s or 1960s.
It would have been used by the military to mark shore positions on exercises, a navy spokeswoman said.
She added: ‘It was found as the result of a child kicking it around on the beach.
‘He kicked it into the rocks and it started to smoke and would not go out on its own.’
The navy took the device to the low tide mark and laid charges around the 2ft-long shell. It was blown up into the air at 8.40pm.
Military marine markers are known to be found around the south coast of England.
They are usually in a metal casing about four inches in diameter and 2ft long, and can burn at temperatures as hot as 2,500C.