The security alert at the Gamblestown Park area of Donaghcloney is now over.
The operation began on Friday afternoon after the discovery of a suspicious object.
It has now been examined and declared to be an old deactivated grenade.
It has been removed from the scene.
A PSNI spokesperson said: “A number of residents who were evacuated from their homes have now returned to their properties.
“Police would like to thank those impacted for their cooperation.”