The Monkees bassist and vocalist Peter Tork died Thursday of unknown causes. He was 77. The news was revealed on Tork’s official Facebook page.

“It is with beyond-heavy and broken hearts that we share the devastating news that our friend, mentor, teacher and amazing soul, Peter Tork, has passed from this world. As we have mentioned in the past, the PTFB team is made up of Peter’s friends, family and colleagues–we ask for your kindness and understanding in allowing us to grieve this huge loss privately. This page will remain open for your use in sharing your thoughts with your fellow fans and hopefully helping you through your own grieving journey, however the team will not be available for some time as we start to mend our own hearts and calm our minds.

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We want to thank each and every one of you for your love, dedication and support of our ‘boss.’ Having you in our world has meant so very much to all of us. Please know that Peter was extremely appreciative of you, his Torkees, and one of his deepest joys was to be out in front of you, playing his music, and seeing you enjoy what he had to share. We send blessings and thoughts of comfort to you all, with much gratitude ~ptfb team”

The band were launched for a TV series, The Monkees, in 1966. Tork was with the band since their beginning, having been cast alongside Micky Dolenz, Davy Jones and Michael Nesmith.

“(Theme From) The Monkees” was one of their best-known tracks, having served as the show’s theme song. Many will also recognize “I'm A Believer,” their 1966 single which was later covered by Smash Mouth for Shrek.

The two tracks were released via their debut self-titled record and More Of The Monkees, respectively. They released nine full-lengths through their initial run until 1971. A greatest hits album was released in 1976, and the band ended up reuniting (sans Nesmith) for the first time in 1986. This was due in part to a revived interest thanks to MTV rerunning the series.

Tork was diagnosed with adenoid cystic carcinoma, a rare head-neck cancer, in 2009 but was later given an all-clear from his physician. He would join the band two years later for a reunion tour.

Tork is preceded in death by Jones, who died of a sudden heart attack in 2012. The band would reunite sporadically over several decades and released four more full-lengths, their most recent in 2018, Christmas Party.

Our thoughts are with Tork’s family and friends at this time.