Las Vegas ? Roy Horn, one half of the illusionist team of Siegfried & Roy, was hospitalized in critical condition Saturday, a day after one of his tigers mauled him during their nightly show, biting him in the neck and dragging him off stage.

Horn remained in critical condition Saturday night at University Medical Center after suffering a serious injury to the left side of his neck and undergoing surgery late Friday.

Hospital officials would not provide any more information, but the mood was somber among the host of Las Vegas notables who went to see the magician.

“I’m pretty much on a vigil,” said Bernie Yuman, the duo’s longtime manager.

Fellow magician Penn Jillette, one of many celebrities outside Horn’s hospital room Saturday, said he understood that Horn was on life support but did not elaborate.

“The overwhelming likelihood is that we’ll have to wait two or three days before we really understand the full extent of these injuries,” Alan Feldman, an MGM Mirage spokesman, said Saturday.

Horn and his longtime partner, Siegfried Fischbacher, have been a Las Vegas Strip staple for years, performing their magic show to sold-out crowds at The Mirage hotel and casino. The shows, with their signature white tigers and lions, are among the best known and most expensive on the Strip.

“For more than four decades, I have had the great privilege of standing at the side of this remarkable man, and I will continue to do so during this very challenging time,” Fischbacher said Saturday.

Halfway into Friday night’s performance, Horn appeared alone on stage with the tiger and told the crowd the animal was making its debut in the show — a claim hotel officials said was part of the act.

Las Vegas magician Roy Horn, of Siegfried & Roy, shows off two 6-day-old additions to his royal white tiger family in this Oct. 28, 2002, photo at The Mirage hotel and casino in Las Vegas. A tiger attacked Horn during a Friday night performance at the hotel. Penn Jillette, a fellow magician, said Saturday that he understood that Horn was on life support.

The tiger, which weighs about 600 pounds, then lunged at Horn, who tried to beat the animal off with a microphone.

“I knew he was in trouble right away. I was horrified,” said Diane Weightman, who was in the audience. “I wanted to jump on stage and help him. I didn’t know what to do.”

Andy Cushman, also in the audience, said Horn “looked like a rag doll” as the tiger dragged him off the stage.

Feldman said stage crew members used fire extinguishers to distract the animal and free Roy.

After the attack, Fischbacher appeared on stage and told the 1,500 audience members the performance was canceled, Cushman said.

Hotel officials said the show has been canceled indefinitely. The tiger involved in the attack, a 7-year-old male named Montecore, was quarantined at the hotel, officials said. Feldman said the animal had been used in the show for several years.

Horn, who turned 59 on Friday, had never been injured during a show before. “Not a scratch, not by an animal,” Yuman said.

The illusionists signed a lifetime contract with The Mirage in 2001. The German-born pair perform six shows a week, 44 weeks per year and have been onstage in Las Vegas for more than 35 years.