China is struggling to clean up its tainted professional football leagues, beleaguered by match-fixing, bribery and online betting, state media announced on Monday.

Police and sporting officials have been urged to smash betting rings, close gambling booths and root out online gaming sites as the country gears up for the Beijing Olympics in 2008.

"We should target those organisers, gambling bankers and people who induce others to bet," an official circular said, quoted by Xinhua news agency.

Controversy has dogged China's Super League -- the top soccer competition -- with administrators admitting last year that corruption is rife in Chinese football.

Established in 2004 to boost the image of the tarnished former Division A games, match-fixing and bribery scandals involving players and referees have alienated fans and sponsors, contributing to disastrous attendances and clubs folding.