Black-clad riot police fired tear gas and beat demonstrators with batons as thousands protested delays to Congo's first postwar presidential elections. The United Nations said at least six died in violence nationwide.

Several thousand demonstrators carrying white banners of the main opposition party marched toward parliament in the capital Kinshasa, fists held high and waving palm branches.

They were met by a phalanx of riot police, who fired volleys of tear gas and gave chase as the crowds scattered.

Dozens of police armed with Kalashnikovs raced into the surrounding neighborhoods, dragging out demonstrators and beating them with batons. The empty boulevard was littered with shoes left by demonstrators who fled police and tear gas.

As police gave chase to fleeing demonstrators, gunshots rang out from the narrow streets, but it was unclear who was firing the shots.

Quoting hospital sources, U.N. spokesman Kemal Saiki said one person had been killed in Kinshasa and seven others wounded. Two more demonstrators were killed and 12 wounded in clashes between police and demonstrators in the central diamond-mining town of Mbuji-Mayi, an opposition stronghold.

Another three were killed and 10 wounded in another mining town Tshikapa, he said.

Opposition spokesman Jean-Baptist Bomanza alleged that government security forces had killed 10 people in Kinshasa and that 100 died in violence throughout Congo.