"FanCheck contains NO malware," Janakan Arulkumarasan said in an e-mail interview with IDG News Service.

Malicious hackers are trying to capitalize on insistent rumors that FanCheck infects users' PCs with viruses, Facebook and security company are warning. These hackers are setting up malware-infested Web sites that falsely claim to remove FanCheck viruses.

When concerned Facebook members use search engines to find antivirus information about FanCheck, they are getting search results that point to these malicious sites, where they are tricked into downloading fake and malicious antivirus software.

"FanCheck is NOT a malicious app. Unfortunately, some malicious developers have been spreading a lie that it is -- and encouraging people to download fake virus scanning software, which damages their computer. This is very unfortunate, but it has nothing to do with us," said Arulkumarasan, who describes himself as a Hong Kong-based entrepreneur.

Facebook has reviewed the application and hasn't found it to contain malware, according to a Facebook spokesman.