Burma’s ruling junta is attempting to seize United Nations computers containing information on opposition activists in the latest stage of its brutal crackdown on pro-democracy demonstrations, The Times has learnt.

UN staff were thrown into panic over the weekend after Burmese police and diplomats entered its offices in Rangoon and demanded hard drives from its computers.

The discs contain information that could help the dictatorship to identify key members of the opposition movement, many of whom have gone underground. UN staff spent much of the weekend deleting information.

The stream of dramatic images of tens of thousands of monks parading through Rangoon inspired condemnation of the Government across the world. On Saturday, demonstrations denouncing the regime were held as far apart as Sydney, Singapore, London and Washington.

Many of the images were disseminated through e-mail by Burmese bloggers who used software to outwit attempts to block them. Even after the Government shut down the internet altogether ten days ago, photographs and films were smuggled out on tiny storage drives and memory cards by travellers to Thailand.

Some of the demonstrators have reportedly been arrested after being identified in footage of the rallies. The junta is going after the UN, in the belief that its officials allowed images to be transmitted through their own internet links – channelled via satellite phones and therefore less vulnerable to interference by the authorities.

“It’s part of this systematic, repressive response to the demonstrations,” said a Western diplomat in Rangoon. “We’ve seen them focus on people who directly participated in the demonstrations by picking them up through the videos Then they’ve arrested people with cameras containing images of the demos. And now they’re trying to track down the means that were used to send them out.”

On Friday Burmese officials went to Traders Hotel in central Rangoon, where several UN agencies have offices. They also called on the Japan International Cooperation Agency in the Sakura Tower. “Police and representatives from the Ministry of Foreign Affairs showed up at JICA and the UN offices at Traders, asking to enter and look at the hard drives of the computers,” a UN official told The Times.

The staff refused their request and asked them to submit it in writing to the UN’s resident co-ordinator in Burma, Charles Petrie. When a formal letter did arrive, it did not mention the computer hard drives, but asked only to see the licences for the UN’s satellite telephone equipment.

Mr Petrie confirmed that the authorities had approached the UN, but denied that this amounted to a raid. “All they asked was to see the permits for the V-Sats [satellite telephones],” he told The Times. “We told them that we will provide them through the appropriate channels.”

UN officials are waiting to see whether the authorities will make a determined effort to seize data and equipment. Such a move would further enrage world opinion at a time when the UN is deliberating on a response to the junta’s crackdown. Today in New York, the UN Security Council is meeting to consider a resolution by the US, Britain and France. A draft reads: “The Council condemns the violent repression by the Government of Myanmar of peaceful demonstrations, including the use of force against religious figures and institutions.” The resolution may be vetoed as “internal interference” by China and Russia.

In London, at least 3,000 people marched to Trafalgar Square to protest against the crackdown. Gordon Brown, the Prime Minster, issued a statement, saying: “The world has not forgotten – and will not forget – the people of Burma.”

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