The bomb squad is on scene after reports a householder found a hand grenade in a garden shed.
Norfolk police said they were alerted at around 10am by the householder who was doing some clearing at home in Burgh Castle, and came across some possible ordnance.
Having forwarded a photograph which was then sent on to the Explosive Ordnance Disposal (EOD) team a crew from Colchester was despatched arriving on scene in Butt Lane at around 2.10pm.
A police spokesman said: 'They reported they had found some items that they believed might be ordnance similar to hand grenades.
'They have sent us photographs that we have sent on and the EOD have come out to check them out.
'They could blow them up or take them away. There are a number of things they can do.'
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