While Australian-led intervention troops moved to establish a presence in East Timor's volatile western region, several arson attacks today provided a reminder that all is not secure here in the East Timorese capital.

A military barracks, a police station, an army warehouse, and two Indonesian government offices went up in flames late this afternoon. The fires, just minutes apart, sent huge columns of black smoke billowing over the city and brought armed Australian troops out in force to restrain the crowds.

Two of the fires--at the warehouse and a branch office of the government's religious affairs department--were next to a compound housing Australian troops.

While no one was seen starting the fires, Indonesian soldiers leaving East Timor have set fire to their barracks and other installations, apparently to keep the facilities from falling into the hands of the foreign peacekeeping troops, or the pro-independence guerrillas who are returning to the capital from their mountain camps.

Establishing a new sense of security in Dili has been the major goal in the 12 days since the first foreign intervention forces arrived. Dili had been ravaged by killing, looting and arson after the territory voted overwhelmingly on Aug. 30 for independence from Indonesia.

To a large extent, the troops have succeeded, with tens of thousands of refugees now returning to Dili from the surrounding hills. Taxis have reappeared on Dili's streets, children are riding bicycles and waving at Australian troops at checkpoints and people are trying to rebuild their damaged homes.

But signs of violence still dot Dili , and today's arson seemed an example.

Local residents immediately blamed the fires on Indonesian soldiers, some of whom are still here guarding a few government installations, and their pro-Indonesian militias, which claim to have infiltrated the local population.

"The militias wear many disguises--you can't tell who they are," said Manuel Verdial, 39, as he watched an Indonesian family planning clinic collapse in flames.

A Portuguese firefighting unit, which arrived here last week, was busy shuttling among today's blazes.

Meanwhile, the intervention troops continued to mount a major buildup in the western area of East Timor around the town of Balibo, with some 700 Australian soldiers now on the ground, backed up by armored vehicles and helicopters. The troops met no resistance, and found no militiamen, although helicopters reported seeing several militia members fleeing across the border to Atambua in western Timor, which is part of Indonesia.

The western areas of East Timor were traditionally the territory's most populated, but the intervention troops today found only about 40 East Timorese in the area, scavenging for food.

The Associated Press reported from Jakarta, Indonesia:

Indonesia's highest legislative body convened today, with the task of choosing the next president, voting on ratification of East Timor's independence vote, and setting the nation on the unfamiliar path of democracy.

After days of student demonstrations demanding further political reform, thousands of police swarmed around the parliament building and at gathering points in the capital as the 700 members of the People's Consultative Assembly took the oath of office.

In a sign of growing impatience with the beleaguered administration of President B.J. Habibie, major party officials agreed to move up the date to select a head of state to Oct. 20.