Police and politicians have condemned the latest attempts to derail Northern Ireland's peace process after a car bomb attack and gun battle involving suspected dissident republicans.

The 400lbs bomb partially exploded after a vehicle broke through a barrier outside the headquarters of the Northern Ireland Policing Board in Belfast.

Nobody was hurt but two men were seen escaping from the area at Clarendon Dock on Saturday night.

In a separate incident, five men were arrested after police exchanged fire with suspected dissident republicans close to the border with the Republic in Co Fermanagh. The Police Service of Northern Ireland detained four in the area, aged 22, 26, 32, and 41, and Gardai the other, aged 27, in Dooard, Co Leitrim.

Forensic officers examine the area around a car which partially exploded in Belfast Full Image

Chief Constable Matt Baggott said Saturday's attacks were designed to derail the political progress. "We have said from day one that the terrorist situation is severe," he said. "This attack is an attack on the well-being of everybody in Northern Ireland, this is not about an attack on policing or the Policing Board, this is an attack on young people and young people's future."

He said in Fermanagh his officers fired two warning shots, which are being investigated by Police Ombudsman Al Hutchinson. He said his officers had been fired at once during the exchange.

It is understood the attack in Garrison was an attempt to kill a police officer who lived in the village. It does not seem that the officer was at home at the time of the attack.

On the Policing Board attack, Mr Baggott added: "It does appear to be a device that has partially exploded, around 400lb. It is a reckless act not just in doing damage but also the potential loss of life."

A car was found burned out nearby in the staunchly republican New Lodge area of the city and police are investigating whether there was any link with the earlier attack at around 7pm on Saturday.

Northern Ireland Security Minister Paul Goggins said: "Very clearly these people are trying to undermine the progress that has been made in Northern Ireland in recent years. When attacks like these happen it brings people together with the strong message that these dissidents will not succeed."