Associated Press, Baucau – Gang warfare has broken out in East Timor's second largest city leaving several people injured, UN officials said on Tuesday.

For the past two weeks, gangs of youths have fought pitched battles in Baucau, 110km west of the capital, Dili, vying for control of city's streets, said Sergey Lashin, chief of the UN's police force in East Timor.

He said one of the gangs had links to the pro-Indonesia movement, which lost in a UN-sponsored independence vote last year.

Officials of the UN Transitional Administration in East Timor, which is preparing the territory for self-government, fear the clashes could lead to widespread criminal violence.

Baucau's bishop, Basilio de Nascimento, said it was imperative that the UN immediately put a stop to the violence.

"I'm a little afraid that all these troubles are caused by the people who are in love with Indonesia," he said. "We need to have law and order." Bishop Nascimento said he expected gang warfare to continue in coming weeks.

Sergio Vieira de Mello, who heads the UN mission, said the violence was motivated by other factors apart from political allegiances. "Unemployment is not the only reason but, I am sure it is part of the problem," he said.