A new virus is infecting Twitter users through the use of URLs shortened by the goo.gl service.

Apparently triggered last night, the virus is spreading as a result of users clicking on links that start with http://goo.gl, Google's URL shortener. TechCrunch is saying that the virus started on Twitter's mobile site and has been growing through different URLs, including http://goo.gl/od0az and http://goo.gl/R7f68.

The virus tries to redirect unsuspecting users to malicious Web sites, according to Techweet, which says that the messages are coming from new, disposable Twitter accounts as well as existing accounts that have been hijacked.

Twitter users have been busy tweeting warnings to each other to avoid clicking on links that may spread the nasty virus. People using Twitter through a mobile phone should be especially wary of any shortened URLs that seem suspicious.

TechCrunch says the tech folks at Twitter are aware of the virus, have been sending out password resets for those affected, and are monitoring the problem.

Shortened links have posed a problem on Twitter and other sites since users can't see the actual URL until they click on the link itself. As such, they've been a favorite trick for cybercriminals who use them to point people to malware-hosting Web sites.

Certain services, such as TinyURL, offer a preview feature so you can see the full URL before clicking on the link. Some browser plug-ins exist that can also preview these types of URLs. And a few antivirus products say they can detect malicious shortened URLs.