This is the image of a 'hand grenade' discovered by workers at the YMCA charity shop in the Arcades shopping precinct in Ashton.
Police were called after the item was discovered amongst items donated to the store.
Nearby shops were evacuated and the bomb squad is on its way from Chester to examine the suspected explosive.
Internet searches reveal practice grenades resembling the one discovered, however, all precautions are being taken.
Drivers are advised to avoid the town centre.
An arrest was made at the scene but it is believed to be unrelated to the grenade being left at the shop.
Shoppers and staff have been asked to assemble at the bus station by police.