21.   In recent years, militant Catholics have tried to block Protestant marchers from entering predominantly Catholic areas, and the confrontations have triggered rioting.

22.   Last summer, confrontations between Catholic protesters and Protestant marchers triggered widespread rioting in Northern Ireland.

23.   More strikingly, the move came just a week after confrontations between Protestant marchers and militant Catholic protesters.

24.   Mrs. Nelson had represented Catholic residents in their fight to block Protestant marchers from parading down Garvaghy Road in the largely Catholic neighborhood.

25.   Mrs. Nelson had represented Catholic residents in their fight to block Protestant marchers from parading down the thoroughfare in the largely Catholic neighborhood.

26.   Mrs. Nelson had represented Catholic residents in their fight to block Protestant marchers from parading down the road in the largely Catholic neighborhood.

27.   On Thursday night, supporters of the thwarted Protestant marchers hurled ball bearings from catapults and threw fireworks at police.

28.   Others found their mark among the ranks of Protestant marchers, who responded by furiously but futilely trying to breach the lines of riot police.

29.   Others hit Protestant marchers.

30.   On Sunday, a standoff between Protestant marchers and Catholic protesters clogged the streets of Bellaghy, a village in the center of the province.