UPDATE Monday, March 5, 2018 (12 p.m.):
The Tennessee Occupational Safety and Health Administration has launched an investigation into what caused a gas leak to evacuate the Smoky Mountain Opry Saturday night.
"TOSHA has opened an investigation into the incident that took place at the Smoky Mountain Opry Saturday," said Chris Cannon, Director of Communications for the Tennessee Department of Labor and Workforce Development.
On Sunday afternoon, it was business as usual at the Smoky Mountain Opry, where the only surprises came from the magic tricks on stage. Less than 24 hours before, there was a different, far more dangerous surprise.
General Manager Michael Headla said that three minutes before the end of the performance, a technician was in a small room behind the stage operating a machine that uses carbon dioxide to create fog and effects for the show.
The CO2 gas leaked into the room and three people had to be taken to the hospital. Two people have been released. UT Medical Center said Monday that one worker remains in critical condition at the hospital.
UPDATE Sunday, March 4, 2018 (7:58 a.m.):
Three theater technicians were taken to the hospital after a CO2 gas leak in the Smoky Mountain Opry, according to a spokesperson from the theater. The leak happened in the special technician room that is separate from the audience.
Pigeon Forge Fire Department says crews were called to the Smoky Mountain Opry around 10:30 p.m. Saturday.
The Fire Chief says crews found three people unconscious inside the building.
Two of the technicians were released from the hospital while the third still is still hospitalized at UT Medical center.
The building was checked and cleared by and reopened by authorities. The theater says that the shows will continue as scheduled today.
Audience members will be able to get a new ticket to see another show.
Smoky Mountain Opry evacuated Saturday evening due to a possible gas leak according to a few witnesses as well as a first responder at the scene.
It is uncertain what may have happened. One witness from Rockwood was at the Smoky Mountain Opry Saturday night. She said she heard a beeping during the performance. The lights also came on during the performance when audience members were being ushered out of the auditorium. The witness also mentioned she saw stage crews still had on their performance costumes as they were exiting the building.
Eric Hutto was also at the Smoky Mountain Opry Saturday evening and was able to get video of people evacuating the building.
A first responder shared with 10News that several people will transported to a local hospital for treatment. It is not known at this time how many people were transported as well as the extent of injuries.
10News has reached out to Pigeon Forge Police Dept. and Pigeon Forge Fire Dept. about the incident but has not heard back about what may have happened at the Smoky Mountain Opry Saturday evening.
10News also has a crew on the way to the scene at this time.
This story is still developing. We'll continue to bring you updates as we receive them.