The Northern Ireland Assembly is today expected to condemn the latest attempts to derail the peace process after a car bomb attack and gun battle involving suspected dissident republicans.

The 400lb 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 in Co Fermanagh.

The Police Service of Northern Ireland detained four in the area and Irish police the other in Dooard, Co Leitrim.

Chief Constable Matt Baggott said Saturday's attacks were designed to derail political progress.

‘We have said from day one that the terrorist situation is severe. We have substantial resources being put into investigating and thwarting these attacks,’ 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.’

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 last night.

The chief constable said that 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, but it is believed the officer was not at home.

The ages of the detained men are 22, 26, 32, and 41.

A suspect arrested by police in the Irish Republic is aged 27.

Earlier this month the Independent Monitoring Commission (IMC) reported that the dissident republican threat in Northern Ireland was at its highest level for almost six years.

The IMC said the two main dissident republican groups, the Real IRA and the Continuity IRA, were working more closely together to increase the threat posed to security forces.

On 7 March the Real IRA killed sappers Mark Quinsey, 23, and Patrick Azimkar, 21, at Massereene Army base in Antrim.

Two days later the Continuity IRA shot PSNI Constable Stephen Paul Carroll in Craigavon, Co Armagh.

In the period covered by the report, 1 March until 31 August, there have been 11 attempts to kill other PSNI officers in Northern Ireland.

Sinn Féin Assembly member Gerry Kelly told the BBC Radio 4 Today programme that he ‘absolutely’ condemned the bombing and urged people with information to pass it to the authorities.

Mr Kelly added: ‘I absolutely condemn it, but I have to say that ritual condemnation is not enough. We need to show political leadership.’

The dissident republican groups responsible for the recent wave of attacks have very little support within the community, he insisted.

‘People are moving on,’ he said. ‘People don't want a return to the place where these people want to bring us back to.

‘We need to close them down. We need to show them that the community is moving on and we are moving on with politics.’

He added: ‘It's ironic that they should choose to attack the Policing Board, which is the very accountability mechanism which was negotiated and set up to keep the police to account and in actual fact holds elected members from every single political party, which means it really is an attack on the community.’

Mr Kelly said the devolution of policing and justice powers ‘would make it very, very difficult for this small number of people in these small groups to have any credibility at all’.

But he said responsibility for deadlock in the process rested with the DUP, whose leader Peter Robinson appeared to be coming forward with new demands in a speech to his party conference over the weekend.

He urged Mr Robinson to ‘face down’ hardliners in his own party.

‘On the issue of transfer of policing and justice, if all the parties brought that together - and it is mostly a DUP responsibility, they are the ones who are holding this up - what a message to give right across the board that we would take control of policing and justice in our own hands,’ he said.

Bomb hoax in Armagh

Police in Armagh, meanwhile, have said that the security alert which caused disruption to the centre of Armagh early today was an elaborate hoax.

British Army bomb experts were called in to examine a suspicious object which was discovered in the Mall in the centre of the city,

The area was sealed off, but the PSNI are now satisfied that the incident was a hoax.