Australian commandos clad in full combat gear flew into East Timor today as the advance guard of an international force called in to prevent a rebellion by disaffected ex-soldiers descending into civil war in the tiny island state.

Around 150 commandos landed at the international airport in Dili, the East Timorese capital. Their first task is to secure the airfield and provide a holding line until the arrival of a larger Australian force including more than 1,000 troops, helicopters and armoured personnel carriers.

The Australian warship HMAS Adelaide was docked in Dili harbour and waiting orders to allow troops ashore. John Howard, the Australian Prime Minister, said the deployment had been fast-tracked: "It’s quite clear the situation in Dili has deteriorated," he said.

The troops’ arrival coincided with growing chaos in the capital as 20 police officers came under fire outside the Justice Ministry by rebels. The street outside was littered with blood-spattered bullet cases and equipment.

So far, five people have been killed in the unrest in a week, including two former soldiers and an army captain today, but many more are feared dead. Most foreign residents have left the country and a South Korean man was wounded in crossfire in Dili today, shot in the neck as he looked out of his window.

"One of the police was shot and his brain burst into pieces. Several other police were wounded," said eyewitness Sampras Soares as the heart of Dili descended further into chaos.

At the Guido Valadares hospital, Dr Augusto Gusmao treated five police officers wounded in the same attack. "All of them suffered gunshot wounds," he said, declining to say how many had been killed.

Hundreds of terrified civilians seeking refuge at the airport from gunbattles in the city - in which three people were killed today - welcomed the Australian Royal Air Force plane with clapping and cries of "Thank God".

The peacekeeping force is led by Lieutenant-General Ken Gillespie, No 2 in the Australian Defence Force, who will negotiate the troops’ rules of engagement in talks with East Timorese government officials.

Other nations are also sending in troops after an appeal for help from the government of the fledgling state. New Zealand said 60 of its police and soldiers were on their way. Portugal, the former colonial power, also agreed to send forces, as did Malaysia

The arrival of the first peacekeepers coincided with a third day of fighting between soldiers still loyal to the government and those troops recently dismissed from service. Exchanges of gunfire rattled across the capital, including areas close to President Xanana Gusmao’s office and the UN compound.

Plumes of smoke rose over deserted streets from homes and businesses torched in the violence.

The latest eruption of unrest in the world’s youngest nation began in March when more than 40 per cent of its armed forces were fired after striking to protest against alleged discrimination in the military.

The sackings triggered riots, with some hardliners fleeing the capital for the surrounding hills where they threatened to mount a guerrilla campaign - similar to that waged during the country's 24-year occupation by Indonesia - if the government did not reinstate them.

The violence is the worst since East Timor won independence from Indonesia in 1999. "We can’t control the situation," said Jose Ramos Horta, the Foreign Minister, as he called for international help disarming the renegades.

Australia has a past record of assisting in the region. It led the UN military force into East Timor after the departure of Indonesian troops and their militia allies in a rampage of violence six years ago. Then the Australian force comprised 1,300 troops, ships, helicopters and armoured personnel carriers.

Fearing the worst, foreigners have begun evacuating the country including 40 staff from the Australian Embassy, together with their families. The US Embassy has also ordered the evacuation of non-essential personnel and advised all Americans to leave.

A South Korean man was wounded in the crossfire in Dili today, shot in the neck as he looked out of his window.

One Australian resident, Margaret Hall, who had been working on a child and mother health project, said she felt sad to go. "I feel horrible, like a rat deserting a sinking ship."

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