Software giant Microsoft is taking legal action against alleged e-mail spammers in the US and the UK.
The company said on Tuesday it had filed lawsuits against 15 alleged spammers, accusing them of clogging its computers and those of its customers with over 2 billion unsolicited e-mail messages.
Thirteen of the lawsuits were filed in Washington state, which has recently passed tough anti-spam legislation, while the remaining two were filed in the UK.
"Spam knows no borders. It is an issue that requires global coordination, so that industry and government have the maximum ability to protect consumers," said Microsoft lawyer Brad Smith.
Spam, which by some estimates accounts for half of all e-mail traffic, is increasingly being seen as a threat to the viability of the internet.
Huge volumes of spam messages can clog up e-mail in-boxes, drastically slowing corporate computer networks.
A high proportion of spam messages advertise pornographic websites, causing offence as well as inconvenience to individual e-mail users.
Microsoft, the world's biggest software maker, has been at the forefront of efforts to tackle the problem, forming an alliance with Yahoo, EarthLink and America Online earlier this year to come up with ways of defeating spammers.
At government level, several US states have passed, or are in the process of drawing up, tough legislation to crack down on spammers.
On the other side of the Atlantic, new European Union rules making spamming illegal are expected to come into force in October.