An old video of Katy Perry singing with Christian metal band P.O.D. has been unearthed.

The 30-year-old singer appears as a performer in the clip, which began circulating all over the Internet on Wednesday, according to Entertainment Weekly.

Perry is seen helping out with the vocals on the band's song "Goodbye For Now" on "The Tonight Show with Jay Leno" in the video dating back about 10 years. She stands in the background at a mic stand behind P.O.D front man Sonny Sandoval. Perry is also featured in the official music video for the 2006 song.

When the "Tonight Show" video first surfaced, several writers were reporting Perry was seen backup singing for the band. In response, P.O.D.'s Marcos Curiel shared a statement with Rolling Stone contradicting the reports.

"This is revisionist history and disrespectful to our girl Katy who was never a backup singer," Curiel said. "We invited her to participate on our record as she was and is still is one of the few pop artists with strong musicianship roots. ... She paid her dues not as a backup singer but in a van going town to town. This is the problem with music journalism today. ... Shabby reporting. No research. No history."

Perry, who is now one of the world's biggest pop stars, first came into the music business as a Christian rock singer known as Katy Hudson. She even released a debut album under that name in 2001.

The singer switched over to pop music with her second studio album "One of the Boys," which produced the hits "I Kissed a Girl," "Hot N Cold," "Thinking of You" and "Waking Up in Vegas." Her third album "Teenage Dream" and fourth album "Prism" have garnered several hit singles as well.

Perry is currently touring South America as part of her Prismatic World Tour.