A pipe bomb exploded outside a police station in Co Armagh last night, the Police Service of Northern Ireland has said.
The blast happened at around 11.30pm near Lurgan police station.
There were no injuries but a nearby building was damaged.
The PSNI said no warnings were received.
Operations Superintendent Pauline Shields said: "This was a reckless and cowardly attack which was aimed not only at killing police officers but also endangering the lives of any members of the public who would have been around at the time.
"This attack must be condemned and I am asking each and every member of the local community to work with us to find those responsible."
Anyone with information about the incident is urged to call 0800 555 111.
PA