BEIJING - A CHINESE anti-virus company has warned against free downloads of Ang Lee's steamy spy thriller, 'Lust, Caution', saying several hundred sites offering the service were embedded with viruses.

The movie has been a big hit in China, reaping 90 million yuan ($17.6 million) in its first two weeks, despite losing seven minutes to the censors, and has been tipped by some to be the year's biggest box office success.

'People should be wary of websites that offer free downloading services because their personal passwords can be stolen,' Li Ting, of Rising International Software, told reporters.

She said several hundred websites promoting 'Lust, Caution' were embedded with viruses and 15 per cent of download links were contaminated.

'Hackers are taking advantage of popular entertainment hotspots for movies and music to attack personal computers and spread viruses,' she said.

An engineer with the compnay was first to encounter the virus last week - his screen went blank and he lost his instant messaging password. -- REUTERS