Panic! At The Disco Drummer Spencer Smith Leaves Band

Brendon Urie and Spencer Smith of Panic! At The Disco
Andy Kropa/Getty Images

Brendon Urie and Spencer Smith of Panic! At The Disco visit fuse Studios on March 24, 2011 in New York City.  

Spencer Smith, the founding drummer of pop-rock group Panic! At The Disco, has announced plans to leave after a decade with the group. Smith's departure means that frontman Brendon Urie is the only remaining member from the band's original lineup.

"To our fans…After 10 years of being a part of this unbelievable journey it saddens me to say that I will be leaving Panic," Smith begins a long letter posted to the group's website on Thursday morning (Apr. 2). "This was not an easy decision to come to, but after a lot of thinking it became clear that this is what's right for me and the band. I love this band with all my heart, and getting to see it grow from 4 kids in my parents garage to what it is now has been incredible. I loved it all. But, at a certain point, I realized that I wasn't able to be there for the band the way I wanted to be, and more importantly, the way they needed me to be."

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Smith also mentions his past struggles with substance abuse, and thanks his bandmates for their continued support. "They helped me through those rough times, and now, on the other side, with two years sobriety from prescription medication, and working on a year sobriety from alcohol, I am nothing but grateful for all they have done," he writes.

Panic! At The Disco exploded on the pop scene in 2005 with the single "I Write Sins Not Tragedies," which reached No. 7 on the Hot 100 chart; the extravagant video for the single won the MTV VMA for Video of the Year in 2006. The group's debut album, A Fever You Can't Sweat Out, has sold 1.98 million copies since its 2005 release, according to Nielsen Music.

Following the group's 2008 album Pretty. Odd., guitarist/songwriter Ryan Ross and bassist Jon Walker split from the group to form the band the Young Veins. Since then, the band has released two more studio albums, 2011's Vices & Virtues and 2013's Too Weird to Live, Too Rare To Die!

Panic! is next scheduled to perform at the FestivALTAZ in Mesa, Ariz. on Apr. 10, with a handful of spot performances slated for the summer. Click here to read Smith's full note to fans.