A new cyber bug that's similar to the highly disruptive "Panda worm" which plagued China's Internet for several months is now trolling the Web for victims, an anti-virus software company reported yesterday.

Security experts at Beijing-based Jiangmin New Tech Ltd said the new worm, known as "Shadow of Panda," is "like a twin brother" to the previous attacker.

Like the previous version, it infects program files and steals the account names and passwords of online game players and popular chat sites.

The notorious "Panda worm" started to spread through Chinese-language parts of the Internet last December. Computer uses knew they were infected if their executable file icons turned into images of a panda holding joss sticks.

Millions of computers were infected across the nation.

The worm was listed as the worst cyber bug last year by Chinese anti-virus developer Rising Corp. It also received the first five-star severity rating issued by the Shanghai Information Technology Service Center because it could attack local-area networks in government bureaus and companies and damage their programs and databases.

The creator of the worm, Li Jun, a 25-year-old Wuhan resident, was arrested - the first time China's cyber cops had apprehended a virus writer. Li confessed selling the panda code to 12 people for 100,000 yuan (US$12,908). The police released anti-virus software written by Li to correct the problem in February.

The unknown creator of the new "Shadow of Panda" has written a line in his code that says, "I despise the commercialized anti-virus companies. The panda is gone; so is creator Li Jun, but I will carry on his unfinished task. I will devote myself selflessly to improving the safety awareness of Chinese netizens."

Jiangmin company said anti-virus experts had found solutions to deal with the new worm and urged Internet users to update their security software.