ANTHRAX recently spent time in the studio recording several cover versions of some of their favorite rock classics, to be included with the upcoming re-release of 2011's "Worship Music", the group's first new album in eight years and first with singer Joey Belladonna since 1990.

In addition to RUSH ("Anthem") and BOSTON ("Smokin'") covers, ANTHRAX also recorded its versions of AC/DC's "T.N.T.", JOURNEY's "Keep On Runnin'", THIN LIZZY's "Jailbreak" and CHEAP TRICK's "Big Eyes", which ANTHRAX guitarist Scott Ian tells Billboard.com may also possibly surface as digital downloads for those who already own the "Worship Music" album.

"It was a lot of fun, especially because a lot of those [songs] aren't, I guess, normal for us or like so much of our repertoire — although they are because they're songs we all knew," Ian explains. "Maybe on paper the idea of us doing something like that seems weird, until you hear them and then it makes sense. And Joey's performance on the JOURNEY song, specifically, really blows my mind. Someone mentioned that [JOURNEY guitarist] Neal Schon better not hear this or we might lose our singer." ANTHRAX also also laid down a cover version of BLACK SABBATH's "Neon Knights" for the upcoming Ronnie James Dio tribute album which is being assembled by the singer's widow and longtime manager Wendy Dio.

Regarding ANTHRAX's upcoming touring activities, Ian tells Billboard.com: "We thought last month was going to be the end of the cycle; that was pretty much the plan at the beginning of last year. [2012] was a really good, busy year, and when we finished in Europe in December we figured that was it. But we keep getting more and more offers to go on tour. We've always been a touring band, so that works in our favor, I guess. In the past we wouldn't think about doing the States four times unless you were selling millions of albums or something. But there's a demand for it, which makes us happy."

"Worship Music" has sold more than 100,000 copies in the U.S. since its September 2011 release, according to Nielsen SoundScan. A track from the CD, "I'm Alive", received a Grammy nomination last month for "Best Rock/Metal Performance". This is the fourth Grammy nomination for ANTHRAX.

As reported on Friday, guitarist Rob Caggiano has announced his departure from ANTHRAX to focus on his other passion: producing records. A replacement axeman has not yet been announced.

Video below: ANTHRAX performing "Neon Knights" live at Copenhell festival in Copenhagen, Denmark on June 15, 2012