A tightrope walker was seriously injured when he fell 40 feet from a high wire in front of a horrified crowd watching a performance of the Jordanian International Circus.

Jorge Humberto Castro, 22, Dallas, lost his balance and fell to the floor, landing on his head and shoulders during a performance at the Utah State University Spectrum on Wednesday night.The show was stopped immediately after the incident as paramedics rushed to help the unconscious and bleeding performer. It resumed after what was called a 30-minute intermission.

Castro was flown to LDS Hospital in Salt Lake City after receiving emergency treatment at Logan Regional Hospital, a spokesman said. He was reported in serious but stable condition in the hospital's intensive-care unit Thursday.

Craig Ebert, an emergency medical technician with the Logan Fire Department, said it appeared many people thought the fall was part of the act until Castro hit the ground.

Children then screamed and many in the crowd of 4,000 "sort of freaked out," he said.

Several audience members said they were shocked that the performer was allowed on the high wire without a net. Others called authorities and local news organizations to get Castro's name to wish him well.

Nora Barker of Providence, Cache County, said she couldn't get the incident off her mind and her young daughter was unable to sleep afterward. They and others planned to send Castro a card.

"Hopefully, it will be good therapy for him," Barker said.