A booby trap bomb placed under the car of a policeman in Northern Ireland was clearly intended to kill, a police commander said tonight.

Police Service of Northern Ireland Assistant Chief Constable George Hamilton blamed dissident republicans for the murder bid in east Belfast.

The latest attack by violent extremists opposed to the peace process has been met by widespread condemnation.

The viable explosive device was found by the officer around 2pm today. His car was parked at his home on the Upper Newtownards Road - a busy arterial route into the city centre.

The scene, which remained sealed off tonight as the security and forensic operation continued, is close to PSNI headquarters at Knock and the Northern Ireland Assembly at Stormont.

Mr Hamilton said: "It is very fortunate that this device was detected before it exploded and that no one was killed or seriously injured.

"Initial investigations would indicate that this was a viable device placed below an officer's car some time in the last 48 hours. It was clearly intended to kill the police officer.

"His family and neighbours in the vicinity were also put at risk of serious harm.

"Obviously there are people out there who are still intent on causing murder and mayhem."

Dissidents have repeatedly targeted security force members in recent years .

In November long-serving prison officer David Black, 52, was shot dead in a motorway ambush in Co Armagh as he drove to work.

A group styling itself the "new IRA" claimed that attack. The faction was formed in the summer when a number of splinter groups joined forces.

In April 2011 newly qualified police officer Ronan Kerr, 25, died when a dissident booby trap car bomb exploded under his vehicle at his home in Omagh.

Mr Hamilton appealed for anyone with information on the latest murder bid to come forward.

"Attacks on police officers are attacks on the entire community and cannot be allowed to continue," he said.

"We know there are people within our communities who know who did this, we know there are people out there who know exactly what is being planned.

"My plea to them is not to allow this small minority to drag us back to the past.

"Our belief is that this attempted murder was carried by those opposed to peace from within dissident republicanism.

"They don't care who they attack, they don't care who they kill. They are simply anti-peace and determined to carry on bringing pain and devastation to families and communities by maiming and killing.

"The community can be assured that the Police Service of Northern Ireland will do everything possible within the law to bring those responsible to justice.

"However it is very important that we get information about this incident quickly. We need support from members of the public in bringing those responsible to justice."

Terry Spence, chairman of officers' representative body the Police Federation, said the device was planted by "cowardly thugs".

"This was an attempt to murder an off-duty police officer," he said.

"But this attack is no great surprise. Scores of police officers have been forced from their homes in the last 12 months because of terrorist incidents. This is just the latest of many.

"It reinforces the need for officers to be extra vigilant."

Residents of nearby homes were evacuated in the alert. A local church opened its doors to offer shelter while army technical officers (ATO) worked to make the scene safe.

On behalf of the UK Government, Northern Ireland Office minister Mike Penning condemned the attack.

"Those who are responsible offer nothing except terror and misery not just to this police officer and his family but to his neighbours and the wider community," he said.

"Thankfully, due to the vigilance of the officer, no one was injured in this cowardly attack. My thoughts are with him and his family at such a distressing time. I also want to pay tribute to the bravery and professionalism of the ATO officers who put their lives on the line by making safe these devices."

Northern Ireland Policing Board chairman Brian Rea said: "I know I speak on behalf of all board members when I express my shock and disgust at what was clearly an attack on the life of a police officer.

"My thoughts and prayers are with the officer and his family today as they deal with what could have been a very serious incident.

"The board continues to be deeply concerned at such attacks.

"I have said before, and I reconfirm, that there is no support for such actions and anyone with information should bring it to the police."

Democratic Unionist Assembly member for East Belfast Robin Newton said those responsible had nothing to offer the community other than "heartache and sorrow".

"The thugs who carry out this type of an action are rejected by the vast majority of the community as being wicked and evil, who care nothing for innocent life," he said

East Belfast Alliance MLA Chris Lyttle said: "My immediate thoughts and prayers are with the officer and family directly affected by this cowardly and futile act and the people working to restore safety to all residents in the area.

"Those behind this incident have absolutely nothing to offer the local community and are only intent on taking Northern Ireland back to a time of deep division through violent attacks.

"Anyone, from whatever background, considering an attack on the PSNI should remember that officers have the full support of the vast majority of people across Northern Ireland. Any attack will only serve to risk misery to families and resolve the will of this community to reject violence in favour of peace."

SDLP Policing Board member Conall McDevitt said the murder bid was a "cynical and deplorable act".

"Those seeking to target police officers are undermining not only the stated will of the people of Ireland who have long since rejected violence, but also the desire for a new beginning for policing in the North, which is shared by the majority of citizens," he said.

Police want to hear from anyone who witnessed any suspicious activity on the Upper Newtownards Road between the junction of Cabinhill Park and Knock Road between Friday afternoon and lunchtime today.