John Hartman, a cofounder of the Doobie Brothers and the California rock band's original drummer, has died. He was 72.

On Thursday, the band announced Hartman's death in posts on its official Instagram and Twitter accounts, where they complimented him as "a wild spirit, great drummer, and showman" and offered condolences to his family.

"Today we are thinking of John Hartman, or Little John to us. John was a wild spirit, great drummer, and showman during his time in the Doobies," the band wrote in its social media posts. "He was also a close friend for many years and an intricate part of the band's personality! We send our condolences to all his loved ones at this difficult time."

"Rest In Peace John," the band added. The Doobie Brothers did not confirm when Hartman died or his cause of death.

Hartman formed the original Doobie Brothers with guitarists and vocalists Patrick Simmons and Tom Johnston in the early 1970s after meeting the pair while playing in Bay Area bars in Northern California, according to the band's official website.

"It all began in 1969, when a drummer named John Hartman arrived in Northern California. He was there to meet Skip Spence from the band Moby Grape and become part of a supposed band reunion that never quite got off the ground," an excerpt from the band's biography on its website reads. "But it wasn't all for naught. Spence (who had also played in the Jefferson Airplane) introduced Hartman to his friend Tom Johnston, a local singer/songwriter/guitarist -and they connected. Hartman and Johnston began playing local Bay Area bars."