Associated Press in Dili – Gangs of youths wielding machetes and clubs rioted on Tuesday in Dili's main marketplace, seriously injuring at least four people, eyewitnesses said.

Heavily armed foreign peacekeeping troops quickly moved into the market to stop the fighting, which broke out early in the morning between two gangs of local youths. A short time later foreign peacekeepers and civilian police were guarding about 30 young men sitting in the street, some still holding knives.

Witnesses said up to 80 people were involved in the fighting. Authorities confiscated the weapons, which were piled in the back of at least one police vehicle.

Troops from the international peacekeeping force in East Timor were conducting a house-to-house search of an area around the market, in central Dili.

Witnesses said they heard two shots fired. It was not known if any of those injured were shot. Ambulances took at least four people away from the scene. Witnesses said one man had serious head injuries.

The riot was believed to be the result of escalating tension between rival groups in Dili and a perceived lack of policing of petty crime.

One gang member, Ajuro, said the territory's fledgling government, known as the CNRT, was not doing enough to protect people in the market. "Every day there are problems in the market and we are not getting any protection from the CNRT," he said

Violence among civilians in Dili has been rising recently, as the United Nations settles into its transitional administration of the territory after the withdrawal of Indonesian military rule last year.