Johnny Depp, Joe Perry and Alice Cooper of Hollywood Vampires attend The 58th Grammy Awards at Staples Center on Feb. 15, 2016 in Los Angeles.

Joe Perry fell ill and was forced to leave the stage during a performance with the Hollywood Vampires in Brooklyn on Sunday (June 10) night, according to reports.

Tweets and Facebook posts from fans on the scene say the Aerosmith guitarist staggered off stage early in the concert and was treated backstage by emergency medics. According to sources, Perry exited the stage during the first song, though the band continued to play. Footage taken at the gig shows a frail Perry struggling to perform, then ducking behind the amp stack (see below).

Frontman Alice Cooper updated fans on Perry's condition. "Thanks to everyone asking about our brother Joe Perry. He is stable right now, with family and is under the best care," Cooper tweeted after the show.

Thanks to everyone asking about our brother @JoePerry. He is stable right now, with family & is under the best care pic.twitter.com/oxCRUqRAk6 — Alice Cooper (@RealAliceCooper) July 11, 2016

The Hollywood Vampires echoed Cooper's sentiments with a post-show message: "Joe Perry is stable and resting. His brother Vampires and fans wish him a speedy recovery," the band tweeted.

Joe Perry is stable and resting. His brother Vampires and fans wish him a speedy recovery. — Hollywood Vampires (@hollywoodvamps) July 11, 2016

During the show, one Twitter user alleged Perry received CPR from a New York City fireman. Former That Metal Show host Eddie Trunk provided some details on the developing story.

Apparently the band is continuing to play. @JoePerry sat down on the riser & then was taken away by EMTs. Be well Joe! More when I know.. — Eddie Trunk (@EddieTrunk) July 11, 2016

According to Facebook fan account AeroFANatic, which cites an on-the-scene source, Cooper said, "If you notice one of our brothers is not onstage with us, he was very sick before the show." New York's ABC outlet reports Perry was taken to the hospital for evaluation. He was later declared stable and transferred to Columbia Presbyterian Hospital, NYPD told ABC News.

Fellow guitarist Tom Morello (Rage Against the Machine, The Nightwatchman) tweeted, "Thoughts and prayers out to the great Joe Perry. Cmon man please be ok we love you love you love you!!!"

Thoughts and prayers out to the great @JoePerry. Cmon man please be ok we love you love you love you!!! — Tom Morello (@tmorello) July 11, 2016

Perry's Aerosmith bandmate and close friend Steven Tyler was due to perform a solo show in Vancouver on Sunday night and has yet to comment on the unfolding situation.

Sources who were at the show say Perry participated in a VIP meet-and-greet about 30 minutes before taking the stage. Though he looked noticeably thin, there was nothing amiss. The rocker became visibly unwell during the band's second song, a cover of Spirit's "I Got a Line On You," when he sat on the left of Matt Sorum's drum riser, stopped playing and exited the stage. Perry was seen to be carried from the room during the third song, a cover of David Bowie's "Rebel, Rebel."

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Later, a crew member appeared on stage and taped what appeared to be a revised set list in front of bassist Robert De Leo, a source notes. The band continued its set without several key songs that Perry had performed at recent shows, including "Stop Messin' Around," a Fleetwood Mac song that Perry sang lead on; Aerosmith's "Sweet Emotion" and the Aerosmith cover of "Train Kept A-Rollin." Cooper told the crowd his bandmates were "improv -ing like a good bar band."

Ian Hunter also joined the band for the encore, playing guitar and doing lead vocals on "Sweet Jane" and "All the Young Dudes." Not surprisingly, the scheduled aftershow meet-and-greet was canceled.

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The Hollywood Vampires were performing at the Coney Island Amphitheater on Sunday night. Their next tour date is slated for Fraze Pavilion in Kettering, OH on Tuesday (July 12). The band is scheduled to make its first late-night appearance Monday night with a booking on The Late Show with Stephen Colbert. Its unclear whether that appearance will go ahead.

A publicist for Perry shared this message with Billboard at 2am ET: "Joe Perry is doing well and resting and appreciates all your good wishes."