A night of arson and reprisals: they even targeted the kitchen sink

Tensions rose considerably in Northern Ireland yesterday as further sectarian petrol bombings took place in Ballymena, Co Antrim, and police warned that a discovery of IRA material constituted clear evidence of IRA plans for pre-Christmas attacks in Belfast.

In Ballymena, two more Catholic schools were damaged in arson attacks, while a gang burst into a Catholic home and attacked a family.

The Ballymena incidents are the latest in a series which have plagued the mainly Protestant town in recent months. There are concerns that police and loyalist demonstrators may come into violent conflict tonightwhen loyalists stage their by-now-routine picketing of the Catholic church in the town during Mass.

Yesterday brought appeals for calm as both the communal tensions and fears of renewed terrorist activity rose appreciably. Sean Farren of the Catholic Social Democratic and Labour Party, warned: "It is essential for the country to draw back from this confrontation and for leadership to ensure that it will not happen again. The situation could escalate still further - that would be very serious not just for the communities in North Antrim, but elsewhere as well."

The first fire broke out at St Patrick's College. The alarm was raised when smoke was spotted by a member of the public and damage was limited. In the second attack, at St Joseph's primary school, outside the town, a passing police patrol noted the fire and tackled it until the fire brigade arrived.

In the other incident, a group of men broke into a house in the Ballykeel area of the town and attacked a Catholic woman, her daughter and a male visitor.

Earlier this week, two Catholic homes in the same street were attacked with petrol bombs.

Meanwhile, a woman was charged with terrorist offences yesterday after the discovery in a house in west Belfast of three mortar bombs, together with incendiary devices and a bag of ammunition. The 35-year-old woman was charged with possession of explosives with intent to endanger life and making a house available for the purpose of terrorism. The woman, who was taken for questioning on Thursday, the day of the find, is expected to appear before Belfast magistrates today.

The mortars are of a type which have been used primarily for attacks on security force bases. They have also been used as "horizontal mortars", when they have been dug into the side of the road and fired point-blank at security force vehicles, causing fatalities in the past. They were discovered along with 34 cassette-type incendiaries of a model which the IRA has previously left in shops and other premises.