Tension high in Belfast after march

Members of the paramilitary Ulster Freedom Fighters mark July 12th in Belfast

BELFAST, Northern Ireland -- Protestors have used bricks, bottles and fireworks to attack security forces during a Protestant Orange Order parade in Northern Ireland.

Elsewhere, hundreds of other similar parades marking "Twelfth of July" passed off peacefully.

The hour-long riot took place near a Catholic housing estate in Ballymena, a town northwest of Belfast.

A police spokesman in the area told CNN: "An Orange Parade of several hundred people was passing the estate when about 200 Catholic protestors tried to move in.

"Bricks, bottles and fireworks were thrown at the police lines."

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In Belfast, Catholics jeered and threw small objects at Protestant marchers as they held a march in the Ardoyne district.

Police later confiscated stashes of crude weapons and warned of possible confrontations when the Orange Order parade returned there later in the evening.

Chief Inspector Colin Taylor warned: "Last year we saw one of the worst riots there have been in Belfast for 20 years in this area and we are doing our best to avoid the same scenario this time around."

Belfast police commander Alan McQuillan has warned that Republicans were planning to bus in hundreds of youths to the area to launch acid and petrol bombs.

Earlier, a bomb was discovered in Belfast city center just before a Protestant march was due to pass by.

Army explosives experts defused the device found in a van at Little Donegal Street.

The Ulster Unionist former Lord Mayor of Belfast Jim Rodgers said: "This bomb quite clearly was designed to kill members of the Orange institution along with band members and spectators."

Orange leaders have condemned violence after last weekend's clashes at Drumcree

The incidents were the only violence reported during the day as tens of thousands of Protestants marched across Northern Ireland.

Orangemen held parades at 17 locations, to be followed by hundreds of smaller parades in the evening.

The "marching season" of 3,500 mainly Protestant parades between Easter Monday and the end of September reaches its climax this weekend.

In a statement, the Parades Commission urged all sides to show restraint.

"The Parades Commission hopes that over the next two days those parading and their supporters will show respect to their host communities and that those communities will demonstrate tolerance and respect of the traditions of the parades.

"It particularly calls on everyone to conduct themselves in a peaceful and lawful way."

July 12 celebrates the victory of the forces of the Protestant English king, William of Orange, over the Catholic king he deposed, James II, at the Battle of the Boyne in 1690, confirming the Protestant supremacy in Ireland.