BT has implemented what it claims to be the world's first fully automated 'spam buster' system that can track down professional spammers and botnets on its broadband network.

The company has signed security vendor StreamShield Networks to deliver its Content Forensics product to scan millions of emails a day.

The system will provide BT with detailed reports on the location and size of spam-related problems originating from its network.

BT believes that around 80 per cent of emails on the internet, equivalent to 6.5 billion a day, are spam.

These emails are not only generated by professional spammers but by botnets of PCs infected with rogue software to form a network that generates vast quantities of unwanted email.

Once the forensics software identifies a spammer it is up to BT's Customer Security team to take action, including terminating rogue accounts and adding offending IP addresses to industry-wide blacklists.

"We are turning the tables on professional spammers and cutting off this scourge of the internet at its source," said Stratis Scleparis, chief technology officer at BT Retail.

"We are delighted to work with StreamShield Networks on this innovative approach which tracks down and reduces spam messages on our network, and at the same time helps our customers overcome the threat of infection by bots."