A dog walker was seen throwing a wartime hand grenade for a pet to chase on a beach in Essex.
An off-duty military explosives expert spotted the walker on the shoreline at Marine Parade in Harwich.
The device was discovered on the shoreline at Marine Parade in Harwich, Essex, today when an off-duty military explosives expert saw it being thrown for a dog to chase.
After setting up a 30-yard cordon around the grenade, the passing bomb specialist alerted the police and coastguard, Press Association reports.
The device was later taken away by explosive ordnance disposal (EOD) officers.
It is the fifth grenade to be found in the area in recent weeks.
Essex Police said a grenade was discovered on Saturday on the beach near West End Lane and The Promenade while three were found near Lower Marine Parade on July 12.
All four were disposed of by EOD officers, who carried out controlled explosions on the beach.
Police have warned beachgoers to take care.
Inspector Paul Butcher said: "It would appear that the grenades might have been in a crate that ended up in the sea during the Second World War.
"That crate might be breaking up or has been disturbed by dredging in the port and has resulted in these five devices being washed ashore along the same stretch of beach.
"We are asking people to be vigilant if visiting this beach and to dial 999 if they find any of these devices. Some of them have been covered in barnacles but the one yesterday looked almost as new despite being in the sea, possibly for many years.
"Anyone who finds a grenade should not touch it or move it but should call police immediately."