KUALA LUMPUR (AFP) - The United States-based Environment News Service on Friday accused Malaysian government hackers of shutting down its website after it ran a story on a new book implicating a senior politician in alleged graft.

"The attack on our site came from a Malaysian government entity as identified by their IP address," Mr Sunny Lewis, editor-in-chief of Environment News Service (ENS), said in an e-mail statement, adding the attack shut down its servers for two hours.

The hacking came after the news service ran a story about plans to publish Lukas Straumann's book, Money Logging: On the Trail of the Asian Timber Mafia despite demands by a law firm representing Tan Sri Abdul Taib Mahmud, a stalwart of the ruling coalition, to withhold publication.

Mr Taib, 78, Governor of Sarawak state and a powerful member of the ruling Barisan Nasional coalition, has faced mounting accusations of enriching himself and his cronies through a stranglehold on the state's economy, charges which he denies.

The book investigates the massive destruction of the Borneo rainforest by Malaysian loggers, described by former British Prime Minister Gordon Brown as "probably the biggest environmental crime of our times".

Malaysian officials were not immediately available for comment.

Sarawak is among Malaysia's poorest states, but Swiss-based forest protection group Bruno Manser Fund (BMF) says Taib could be worth as much as US$15 billion, which would make him one of the world's richest people.

The authorities in Sarawak have previously threatened to jam Radio Free Sarawak broadcasts that focus on alleged graft by the state government.

The service was founded by Mr Brown's sister-in-law Clare Rewcastle Brown.