Serbian police yesterday raided the Belgrade headquarters of the Otpor (Resistance) student opposition movement taking away computers, files and campaign material.

The same day two Otpor activists were arrested in Sabac in western Serbia while putting up posters advertising a rally for an opposition candidate in the coming presidential elections. After his release, one of them, Darko Pavlovic, stated that he had been beaten on the legs by the police slapped several times and had his head banged against a window sill.

'The world cannot continue to turn a blind eye to the particularly serious situation outside the capital,' Amnesty International said, adding that simply wearing an Otpor T-shirt has earned some students a beating by police. 'Police ill-treatment and harassment of Otpor and other students and their sympathizers must stop,' the organisation said.

'All incidents should be investigated and those responsible must be brought to justice.'

Background The Belgrade raid was apparently conducted without a warrant by 10 police officers, some in plain clothes, who removed materials including 60 boxes of stickers and other publicity materials, and 10 boxes of Otpor T-shirts. Two computers and their associated hard drives, floppy discs, video and audio cassettes were also removed.

The police reportedly referred to the Belgrade raid as on 'an illegal mercenary pro- NATO organisation'. Over 111 Otpor activists have been arrested since 1 August, when the organisation launched its campaign to support the opposition in the run-up to the Presidential and Serbian elections, due to take place on 24 September.

Even before the election campaign was launched, increasing numbers of Otpor members were arrested, taken for 'informative talks', and then released without charge. Over 400 such arrests took place in May and June alone. Many of these incidents have been accompanied by allegations of ill-treatment - including assaults on minors - at the hands of the police and private security guards associated with the ruling parties. The incidents are particularly frequent in opposition-controlled towns outside Belgrade.

Since its foundation in 1998 Otpor has grown into one of the most vociferous critics of the government in Serbia, organising repeated small-scale protests, which have attracted widespread public support. It recently tried to register as an organisation, but was refused by the authorities.

Pressure on others voicing opposition, mainly in the media, has been steadily increasing since 1998, while other non-governmental organisations have also been subjected to ill-treatment of their members and confiscation of computers and documents by the Serbian Financial Police.