A new e-mail virus has been released on the internet in the latest cyber war of words between rival hackers in India and Pakistan.
E-mail worm is revenge in cyber squabble
A variant of the Yaha internet e-mail worm has been written by a group of hackers calling themselves the Indian Snakes.
It has been attacking websites in Pakistan, including government sites, internet service providers and the Karachi Stock Exchange, said anti-virus firm Sophos.
Yaha-Q arrives as an e-mail attachment and can send itself to people listed in the recipient's e-mail address book.
It then launches a denial-of-service attack - where the ear-marked servers are overloaded by multiple requests - on Pakistani websites.
Unfortunately childish squabbles like this are being fought on the computers of innocent computer users
The worm has also been leaving anti-Pakistani messages on hard drives, although one such message suggests that the hack is not politically motivated.
Rather the spat seems to an attempt to see who is the better hacking group.
"Unfortunately childish squabbles like this are being fought on the computers of innocent computer users, uninterested in the disagreement," said Graham Cluley, Senior Technology Consultant at Sophos.
The damage done by the worm has been fairly limited, said Mr Cluley, and protection is available from anti-virus firms.
An earlier version of the Yaha worm appeared in January affecting computers in over 100 countries.
According to e-mail filtering firm MessageLabs one in around every 200 e-mails sent in 2002 contained a virus.