Jonathan Head reports on the rise of separatist sentiment in Indonesia"

Mr Horta said about a dozen viruses were being designed to infect computers if there is fraud in the 30 August ballot on the territory's future.

The Nobel laureate warned that a 100-strong team of hackers in Europe and North America had prepared a campaign that would cause economic devastation to Indonesia.

Mr Horta: Barred from East Timor during campaigning

Their targets would include computers controlling banking, finance, the military and aviation, he said in a commentary in Australia's Sydney Morning Herald.

"One computer wizard recently told me, 'We will terminate their banking system. We will invade their sites and destroy them...We will cause them to lose hundreds of millions of dollars'," he added.

Electoral fraud

The warnings come as East Timor prepares to choose between Jakarta's offer of autonomy or full independence.

The BBC's Clare Doole: Mr Horta says the hackers would cause massive economic damage

The United Nations which is overseeing the ballot says it is confident there will be a free and fair vote.

But Mr Horta has warned that the ballot could turn into the biggest electoral fraud in modern times.

He said Indonesia's army intended to get a pro-integration vote through by terror and fraud.

Mr Horta alleged that a violent campaign by pro-Jakarta militias had already

• cost over 1,000 lives

• razed entire villages

• uprooted 80,000 people

He said the vote was also compormised by

• a ban on detained resistance leader Xanana Gusmao and himself during the campaigning

• continued Indonesian army support for the militias

• a biased Indonesian controlled East Timorese media

"All this makes for an extremely dangerous situation. Full-scale violence before or after the ballot is now almost certain," Mr Horta added.

Militiamen hand in weapons

''The next phase of resistance will be much more desperate and ferocious and will not be contained to East Timor," he added.

Mr Horta's comments came as Amnesty International also warned that Indonesia's failure to halt the bloodshed in East Timor - mainly by pro-Jakarta militias - threatened to prevent a fair ballot.

Indonesia invaded East Timor, a former Portuguese colony, in 1975 and annexed it the following year in a move not recognised by the UN.