A live hand grenade was found in a garden on Friday, forcing the evacuation of neighbours from surrounding homes.
The device was found by the owner of a house in Coventry Road, Ilford, as he tended his garden.
The police were called shortly after 2pm and it was decided the object posed a "major threat" to the area.
A makeshift shelter was organised in a small hall in Perth Terrace for the safety of evacuated residents.
Coventry Road was closed, an investigation was launched at the scene and an explosives officer was called to safely dispose of the grenade.
It was taken away for forensic examination while residents were allowed to return to their homes by 5pm.