Update [1:50 p.m. EST]: Perry remains hospitalized as of Sunday afternoon, where he is “alert and responsive” according to his representatives. According to the statement, “Perry experienced shortness of breath” before being treated by paramedics backstage, although no official diagnosis has been revealed. Perry has cancelled his Sunday appearance at Rock And Roll Fantasy Camp in Florida but is expected to return by the time his solo tour kicks off on Nov. 30.

Aerosmith guitarist Joe Perry has reportedly been hospitalized after sitting in as a guest performer during a Billy Joel concert at Madison Square Garden in New York City on Saturday night. According to TMZ, the 68-year-old guitarist was carried out of the midtown Manhattan arena on a stretcher with an oxygen supply after collapsing following a sit-in performance of Aerosmith’s “Walk This Way” with Joel during the latter half of the 23-song concert.

Paramedics reportedly gave Perry emergency assistance in his dressing room backstage with use of a tracheal tube down his throat to improve the flow of oxygen. He was eventually wheeled out of the venue after about 40 minutes of being assisted before being taken to a local hospital. It’s not exactly clear at what point Perry collapsed, but Joel was supposedly unaware of the chaos taking place backstage in the “final minutes” of the concert. The teams for both Perry and Joel—as well as Aerosmith—have yet to make an official statement on Perry’s condition as of 1 p.m. EST on Sunday afternoon.

Billy Joel w/ Joe Perry – “Walk This Way” – 11/10/2018

[Video: Brian Paul]

News of Perry’s health emergency on Saturday follows his previous concert collapse back in July of 2016 when he fell unconscious backstage during a show (also in New York City) at the Ford Amphitheater at Coney Island Boardwalk while playing with his other side band, The Hollywood Vampires. Perry would miss almost two week’s worth of shows on their summer tour before returning after his collapse, which the band stated was a result of exhaustion from his busy performance schedule that summer.

Perry had actually shared an image of himself and Joel working out song arrangements backstage to his Twitter page at 11:43 p.m. on Saturday, leading to the presumption that his collapse must have taken place shortly thereafter. News of his condition might have an effect on his upcoming North American solo tour alongside Aerosmith guitarist Brad Whitford, which is scheduled to begin later this month in Sioux City, Iowa.

[H/T Spin]