The bomb squad, police and firefighters are at the scene of an incident in Tameside.
Activity is centred on a section of the Ashton Canal, off Edge Lane, in Droylsden.
GMP said a ‘suspected historic mortar round’ was found in the water at around 2.40pm on Sunday (December 6).
A Greater Manchester Fire and Rescue Service spokesman said crews were called as back up. One appliance has been deployed, they added.
Police set up a large cordon in the area before bomb disposal experts arrived to assess the device.
This is a breaking incident