Mark Dodd, Dili – A day after United Nations riot police swooped on armed gangs running amok in Dili, UN peacekeepers have raised concerns about another potential law and order problem: military-style neighbourhood watch groups.

The groups of East Timorese independence activists are mostly concentrated in the western border districts, where they watch for militia movements or infiltration.

In Suai, in the south-west, about 500 are active. They are known locally as the FSP (Political Security Front). In adjacent Ainaro a similar number are identified by the Portuguese acronym SSR, and in western Maliana the group is called SISN (National Security Information Service).

Under the terms of the UN mandate covering East Timor, law and order is the responsibility of Civpol (Civilian Police), while external security threats are dealt with by the multinational peacekeeping force.

The peacekeepers and UN police have received good co-operation from the indigenous security groups, but there are concerns they could take law and order into their own hands.

"It is a neighbourhood watch that could in time develop into something more militarised," Brigadier Duncan Lewis, the Australian commander in charge of the UN's western border sector, said yesterday.

Civpol officers in Suai said they had detected increasing numbers of pro-Jakarta militia trying to return to East Timor, often by changing their names. Groups like the FSP in Suai are active in screening new arrivals.

About 250,000 East Timorese were forcibly taken to Indonesian West Timor during the violence that followed last year's independence ballot. About 100,000 remain in West Timor, including ex-militia now wanting to return home.

Brigadier Lewis said he was waiting for a report from Indonesian authorities over their claims last week that armed independence supporters had crossed into West Timor to harass the families of militia.

"It is the first report we've had of something like this. I am not saying it could not happen. It is under investigation by Indonesia, and I am anxious to hear what the results are."

On Sunday night and Monday morning, armed UN riot police backed by peacekeepers worked to clear Dili's central market area of scores of armed youths after the worst violence seen in the capital since last year's militia killings.

The UN's top military commander in East Timor, Lieutenant-General Jaime de los Santos, is likely to quit this month and return to the Philippines and a senior defence staff appointment, a UN official said.