A key member of a British Invasion band with several beloved classic hits has retired from touring following a stroke, the group has announced.

The Zombies broke the news to fans Thursday that founding member Rod Argent had been hospitalized overnight and released after falling ill. “Doctors have advised that Rod will need several months of rest and recuperation,” the band said in a statement distributed to news outlets and shared on social media.

Formed in 1961, the Zombies added several undeniable classics to the rock canon of the era: “She’s Not There,” “Tell Her No” and “Time of the Season.” The were inducted in the Rock and Roll Hall of Fame’s class of 2019.

Billboard.com reported that keyboardist and vocalist Argent “stepped away from the group in 1975 in order to focus on his family and being a songwriter, but agreed to temporarily fill in for a few shows in 1999 — something that turned into 25 more years of touring and recording with the band.”

Band managers Chris Tuthill and Cindy da Silva said in the press release that Argent had already been planning to wind down his touring work due to health concerts. Before falling ill, he had celebrated his 79th birthday and his 52nd anniversary with his wife, Cathy. He will continue to write and record with the band, but the retirement takes him out of a planned U.S. tour that he expected to be his last. The stroke “was an unmistakable warning sign that the risks are too great,” said the statement.

The band’s announcement said that all upcoming fall tour dates will be canceled. But the group still expects to hold its second Begin Here Festival this November in St. Albans, U.K.

“We have witnessed hundreds of times how Rod transforms back into an 18-year-old during the 100-minutes he’s on stage each night with The Zombies,” Tuthill and da Silva wrote. “The energy he receives from his musical symbiosis with the current lineup – original singer Colin Blunstone, drummer (and cousin) Steve Rodford, guitarist Tom Toomey and bassist Søren Koch – is doubled by the energy that flows back from the audiences, with fans of all ages joyfully singing along to their classics and new songs. Each year, we’d secretly marvel at how this band could possibly be playing at an even higher level than the previous year, instead of diminishing with age. That being said, the other aspects of touring can be grueling, and can take their toll on 18-year-olds, never mind a musician approaching 80. As heart-breaking as this is for us, the band, our crew and our team, we are a family and fully support Rod in this decision.”

“Our last message is that if a classic artist that has made music you love is performing nearby, don’t miss the opportunity to see them,” write Tuthill and da Silva. “You can sit on the couch and binge Netflix another day. The communal experience of a live performance by a veteran artist is a singular and joyous moment. These artists are treasures who have stood the test of time and are giving their all, but they are fragile human beings like all of us. Don’t miss out.”