A St John spokesman confirmed a man was taken to Waikato Hospital in a serious condition after the incident at 7pm. A Waikato District Health Board spokesperson confirmed the man, 30, was this morning in a stable condition in a ward.
McGregor said the performer, Fiso, was being supported in hospital by his wife and manager. The extent of his injuries were still being assessed, he said.
"The biggest concern for us whether the guy is okay ... we hope that it all turns out okay. Apparently he's comfortable and in good spirits."
McGregor said Fire It Up director Sopi Jensen notified WorkSafe of the incident this afternoon.
"Fire It Up has been in operation since 2011 and its director Mr Jensen has been performing these types of performances for 30 years without any previous accidents of this nature," McGregor said. "Fire it Up has a health and safety policy to cover performances."
On its website, Jensen describes the act as a "fire knife", a traditional Samoan cultural implement composed of a machete wrapped in towels on both ends which are then set alight. The performer dances "while twirling the knife and doing other acrobatic stunts".
Chad Hooker, Hamilton City Council major events director, said in a statement a Polynesian fire performer was injured in the incident which was witnessed by members of the public - including a doctor and an anaesthetist - who were able to provide immediate first aid on the scene.
"Council staff were also on the scene and followed our relevant procedures for an incident of this kind. The performer was then transferred to Waikato Hospital by ambulance where he is recovering from burns to his leg."
Although the responsibility for the safety of the performers sat with the company, council would review the incident as part of its event debrief.
"All performers at the game and venue were arranged by Hamilton City Council as part of the event. The company we used to arrange the performers is a professional talent booking agency and provided all the relevant health and safety information to us as part of the booking.
"Safety of the performers and, in particular, managing the risks associated with their performances sits with the companies and/or performers we hire. In this instance we are confident the company we used had all health and safety aspects covered."
Hooker said council staff wished the man a speedy recovery.
"Our thoughts are with his family and friends - we understand he has family support. The young man was a paid performer, not a council staff member or volunteer."
Neither police or fire were called to the incident.
A paramedic stationed at the stadium was called to the incident, before an ambulance was called.
Mark Brown, who owns the Hamilton hot air balloon which was set up near the fire performers last night, said he was unaware anything had happened until an ambulance turned up.
Brown said the theme of the event was fire, "firing up for the Chiefs".
Fireworks were also let off from the top of the Wel Network Stand when the Chiefs ran on to the field just prior to kick-off.
Chiefs rugby were contacted for comment but were unaware of the incident. The Herald is awaiting comment from Jensen.
H3, a division of Hamilton City Council, operates FMG Stadium Waikato.
