Fierce clashes near Belfast school

A nail bomb and petrol bombs were thrown during violence on Tuesday night

BELFAST, Northern Ireland -- Two police officers have been injured during clashes between rival Protestant and Catholic mobs in Northern Ireland.

A nail bomb and a number of blast bombs were thrown at police lines on Tuesday evening during disturbances close to the area where loyalists are engaged in an ongoing protest to prevent Catholic children going to school.

Petrol bombs have also been thrown at the police, while a burst of automatic gunfire was heard in the area, the Press Association reported.

Earlier in the day, parents and children going to the school ran the gauntlet of police and protesters for a second day, causing some girls to retreat in tears.

Students of the Holy Cross primary school for girls -- some as young as four -- were in tears and at least one parent reported stones being thrown as he tried to escort his daughter to class.

Some parents determined to take their girls through the school's front door rather than the back entrance recommended by school governors led their girls up a street strewn with rubble from overnight rioting.

But the parents and children eventually turned back despite the efforts of riot police to hold back the protests.

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About a third of the school's 150 girls, aged four to 11, made it into school for classes on Tuesday.

Education officials said some lessons had taken place and "a school day has been had."

"It was OK because we went round the back way, and Monday was a terrible experience for me walking up through there and I'll never do it again," said student Corinna O'Kane. "It was just terrible."

One officer was taken to hospital with a shattered collar bone after a home made grenade exploded within the police cordon.

"It is unbelievable in the 21st century that we have to have this type of situation to get kids to school," said Gerry Kelly, a senior figure in Sinn Fein, the republican political party.

Protestants, who are a minority in the Ardoyne area of north Belfast, have said their action is in retaliation for attacks on their homes by Catholics.

The Royal Ulster Constabulary, the provincial police force, said 21 officers were injured during clashes on Monday night, and that rioters had thrown more than 100 petrol bombs.

Police reported five gunshots fired from the Protestant side and three from the Catholic side.

The school governors met with parents on Monday night and recommended using a back entrance that is not vulnerable to protesters. But the school's chairman, the Rev. Aidan Troy, told The Associated Press that some parents resisted.

Northern Ireland security minister Jane Kennedy said it was for the local communities to "back off" and resolve their differences by peaceful means.

"There is absolutely no grievance that can justify that kind of behaviour. It cannot be acceptable," she told the BBC.

Some parents still wanted to use the front entrance on Tuesday

Ulster Unionist leader David Trimble called on the Northern Ireland social development minister Maurice Morrow to convene a special forum to housing and social deprivation issues which were part the problem in north Belfast.

The scenes at the Holy Cross school, he told the Press Association, were unacceptable and overshadowed genuine concerns to Protestants living in the interface area.

Mr Trimble added: "The present situation is appalling. There is a serious danger that the problems could spread to other schools in the area." The leader of the Church of Ireland, Archbishop Robin Eames, also urged all sides to compromise.

He told PA: "No society has the right to deny young children access to education, and it is tragic beyond words to see that the troubles of our community now affect young children of schools in north Belfast."

Dr. Eames added: "While I know there are great complexities to this situation, nothing can possibly justify attacks on little children of any denomination."