A powerful new computer virus, "Nimda", has attacked the financial portal of the Swiss Post, as well as home and business computers elsewhere, officials said.
Because of the virus, services normally offered on the Swiss Post's financial portal, Yellowworld, were unavailable, said spokesman Alex Josty. The system was disconnected to protect the security of the post office's clients.
Because of the infiltration of the worm, which reproduces rapidly, Swiss Post clients have been unable to make payments over the Internet service "yellownet", Josty said.
Nimda has struck a number of countries around the world. It is spread through infected e-mails and Web sites - and particularly by downloading affected documents.
"Nimda infection on Web sites is spreading rapidly," said a spokesperson for Trend Micro, a leading US-Japanese anti-virus software maker.
Virus struck Microsoft unit
It first appeared in the United States on Tuesday but has since burrowed into networks in Japan and the rest of Asia, crippling several corporate systems in the process. The virus has struck Microsoft Corp's Japanese unit, officials said.
In the US, some 130,00 web users and personal computers have reportedly been infected.
Computer experts say Internet traffic has not dropped significantly, although some corporate networks have reported that it has slowed.
Infected email may arrive without a subject line or message, but it may have an attached audio-file called "readme.exe".
Like its predecessor, the Code Red worm, Nimda causes excess traffic on the Internet, which results in a massive slowdown.
swissinfo with agencies