Peter Tork, the bassist for 1960s rock favorites the Monkees, is dead at 77.

Tork's cause of death is not yet public, though he was diagnosed with a rare tongue cancer, adenoid cystic carcinoma, in 2009.

Tork's Monkees bandmate Micky Dolenz confirmed the news on Twitter, writing, "There are no words right now...heart broken over the loss of my Monkee brother, Peter Tork."

The band's official Twitter also paid tribute to Tork with a clip of the singer. "@TorkTweet has passed peacefully at the age of 77. We'll be remembering him throughout the day. Share your favorite memories of Peter below."

Peter Halsten Thorkelson was born in Washington, D.C., on Feb. 13, 1942. A talented multi-instrumentalist, he moved to New York after attending college and became part of Greenwich Village's famed folk scene of the early '60s. Tork auditioned for the Monkees, the fictitious pop group that was formed for the television sitcom of the same name, after his friend – and soon-to-be rock 'n' roll great– Stephen Stills suggested he try out for the show.

Along with Davy Jones, Dolenz and Michael Nesmith, Tork would become one of the founding members of the Monkees, appearing with his bandmates on the program between 1966-1968. With hits including "Last Train to Clarksville," "I'm a Believer" and "Daydream Believer," the Monkees were one of the highest-charting acts of the late '60s.

In honor of Tork's iconic work on the show, MeTV Network plans to pay tribute with a special presentation of "The Monkees" on Feb. 24 (5 EST/PST). "Laugh along with two stories centering around Peter," the network tweeted Wednesday.

Tork left the group and TV show in 1968, teaming back up with Jones and Dolenz in 1986 for a successful 20th anniversary tour. In the years after, Tork largely played with his groups Peter Tork Project, The Dashboard Saints and Shoe Suede Blues. Tork also pursued acting, appearing in episodes of shows including "Boy Meets World," "7th Heaven" and "The King of Queens" in the 1990s and early 2000s.

Following his cancer diagnosis, Tork wrote about his disease in a 2009 essay for The Washington Post.

"I don't count myself as being afraid to die, but the news hit me like a fist to the chest," he wrote, describing his decision not to cancel his live shows after undergoing surgery. "I know I'm taking a chance here, because one of the side effects of the radiation is supposed to be hoarseness," he wrote. "The radiologist told me, 'Well, you play guitar and you sing. Perhaps you won't sing, but maybe you'll play guitar a lot more.'"

In 2016, the Monkees released “Good Times!,” their first album in 20 years, and their first since Davy Jones died in 2012.

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