Police have blamed dissident republicans for an explosion in Lurgan that has been branded an attempt to kill PSNI officers.
Detectives last night released without charge a 46-year-old man they had been questioning at the PSNI's serious crime suite in Antrim in connection with the failed murder bid.
The blast happened at the junction of North Circular Road and Levin Road shortly after 3pm on Saturday. Police were in the area responding to information that an un-notified parade was to take place and two armoured police Land Rovers were parked close to the scene of the blast, although no one was injured.
The attack coincided with a dissident republican gathering at a graveyard in the town in which a masked terrorist made a speech to dozens of supporters threatening further violence.
The device was hidden in a dog litter bin which was destroyed by the blast. Shrapnel and debris were scattered over a wide area.
PSNI Chief Inspector Anthony McNally said: "Those involved in this attack have no place in modern day Northern Ireland. They showed a blatant disregard for the local community, as anyone could have approached this bin as it exploded.
"We want to reassure the community that we will not be deterred by this attack by individuals intent on dragging us back to the past. Local police will continue to deliver the personal, professional and protective service that the vast majority of residents in the north Lurgan area want to see."
Police were attacked with petrol bombs during a follow-up operation in the Kilwilkie area of Lurgan early yesterday morning.
Deputy First Minister Martin McGuinness condemned the attack in a Twitter post and said "anti-peace extremists" were "living in a fantasy world".
His Sinn Fein party colleague, John O'Dowd, said he believed the incident was an attempt to murder police officers which could have had devastating consequences for the public.
He said: "We are thankful that this bomb did not injure anyone but it could easily have been a different story. These individuals continue to show complete disregard for the public.
"The planting of this device along a busy road on one of the busiest days of the year was not only callous it was stupid."
Alliance MLA Trevor Lunn also hit out at the attack. He said: "The people responsible have no place in our society. There can be no justification for any attempt to bring violence on to our streets."
The explosion came just hours after a pipe bomb attack on a house in Bessbrook. No one was injured although a van parked outside the property in Ardaveen Park in the town was damaged in the incident at midnight on Friday.
Meanwhile, a security alert on the Shore Road in Newtownabbey was an elaborate hoax.
The road was closed in both directions after the discovery of a suspicious device close to the junction of the Doagh Road and Hazelwood roundabout on Saturday.
Information about any of the incidents can be passed to police by ringing 0845 600 8000 or Crimestoppers on 0800 55 5 111.