A projectile which was fired from a mortar tube aimed at Craigavon Police Station has been found on a nearby piece of wasteland.
The mortar tube was found at the rear of Brownlow Health Centre
The mortar tube was found at the rear of Brownlow Health Centre across the road from the station.
Police said the device, which they described as viable, was dealt with by Army bomb experts.
Detective Superintendent Derek Williamson said it could have caused serious injury or death.
"I strongly condemn such irresponsible action, the blatant disregard for human life is deplorable and completely unacceptable," he said.
Meanwhile, the police have been dealing with two separate alerts at Strabane and Newtownstewart in County Tyrone.
In Strabane, a "viable device" found at a pub at Cloughcor has been taken away for examination.
In Newtownstewart, police have closed off a minor road in a security alert.
The Strahulter Road was closed following a warning that a device had been left in the area.