By Dominic Casciani BBC News Online in Northern Ireland

After a summer of violence in north Belfast, are the Catholic and Protestant communities heading into more conflict? The second of a two part report.

 Click here for our first report on conflict in north Belfast

The street outside Ardoyne's advice office may be littered with signs of youths taking out their boredom on their environment, but inside it's a model of activity.

It does not just serve some 7,000 Catholic residents. On the wall behind the reception are thank-you-cards from Protestants who comprise 10% of the local population and live just streets away.

Only, thanks to the growing distrust which exploded into clashes at Holy Cross School on Monday, the contacts between the communities are dwindling.

Rather than reaching out to each other, the people in north Belfast are withdrawing behind peace lines.

People from both sides have and are leaving out of fear. The fear may have slightly differing causes by different things - but it amounts to the same thing in a deeply divided community

Father Aidan Troy

Ardoyne may be overrun with social problems but the nationalist community likes to think that it has a sense of cohesion and optimism about the future.

"While nationalists are justly proud of the work we do here, we don't do it just for ourselves," said Elaine Burns, one of the workers at the advice office.

"I don't see any way that we can end the fear and tension without working together and that is why the community workers here are non-political and have spent a long time working in the Protestant community."

But while there are many who believe that slowly and surely Ardoyne could be on the up, it has a bloody past which has given it five of the 17 Belfast peace lines which separate the communities.

Infamous reputation

Protestants generally remember two aspects of Ardoyne's republican history above all others. They remember the support its community gave to the newly born Provisional IRA in 1970.

They remember it for Thomas Begley, the IRA bomber who blew up himself and nine Protestants in a fish shop in 1993 as he attempted to kill loyalist paramilitary leaders.

Elaine Burns: Community worker

Violence and distrust are once more at the fore in Ardoyne.

Loyalist paramilitaries opposed to the peace process have attacked Catholic homes. Some residents have fled. Some republicans have retaliated by intimidating Protestants using Ardoyne's shops.

In turn, loyalists reportedly verbally abused and jostled Catholic community workers visiting Protestants homes. By the summer, the Holy Cross school dispute ahd surfaced.

Following the massive riot on 12 July, the IRA is understood to have warned some prominent Catholics that they were personally at risk if they strayed into "loyalist territory".

But many Loyalists believe that republicans, led by Sinn Fein's well-oiled political machine, are orchestrating a campaign to blame all the violence on their community and push Protestants out. But is that the whole story?

Taxi driver death

Last December, Protestant taxi driver Trevor Kell was shot dead in Ardoyne and the finger of suspicion immediately fell on the IRA.

Forensic evidence linked the bullet with an IRA shooting in 1997. The RUC blamed republicans for the death, but could not say that it was planned by the IRA.

Republicanism: Runs deep in Ardoyne

Some time later, the IRA was blamed for the "punishment shooting" of two men, one of whom is believed to have been questioned over the death of Mr Kell.

Some in the nationalist community suggest that not all of Ardoyne's republicans are happy with the peace process - and Mr Kell's death was proof of fragmentation - fragmentation that the IRA quickly stamped upon.

Upping the ante

In the days before the violence flared outside Holy Cross school, there were clear indicators of what was about to happen.

The kids around here should have more respect for their flag - and how the flying of that flag is interpreted by the other tradition. All it does is up the ante

Catholic resident, Ardoyne

Youths from both communities played an extremely dangerous game of upping the ante, raising more and more flags along Ardoyne Road.

The demarcation of territory didn't win anything like universal support - one local woman described it to the BBC as "no better than dogs peeing on their territory".

Father Aidan Troy, Ardoyne's parish priest, said that people from both sides were already leaving out of fear.

"The fear may be caused in each community by different things. But it amounts to the same thing in a deeply divided community: distrust, instability and uncertainty.

"We have to find ways of tackling that fear and perceived provocation. We are seeking to do it through the churches but others must act too."

 Click here for our first report on conflict in north Belfast