Mexican professional wrestler and actor Cesar Barron, known as Silver King, has died after collapsing in the ring at a show in London.
Barron, who starred opposite Jack Black in the 2005 comedy film "Nacho Libre," was performing at the Roundhouse on Saturday night when he suffered a cardiac arrest.
Tributes have been paid from Mexico and around the world to the former World Championship Wrestling star, 51, with Black among those taking to social media with the words "go with God my brother."
Fellow Lucha Libre fighter Jorge Rodriguez, known as El Hijo Del Santo, was also at the London show and tweeted, "he went as he would have wanted -- fighting!"
WWE star William Regal, Barron's friend and former colleague, posted his own tribute to the wrestler, who he described as "the great Mexican luchador."
Barron collapsed after a kick to his side in the middle of a match with former WWE star Juventud Guerrera, competing under the ring name Warrior Youth.
Footage posted on social media showed initial confusion in the ring before Silver King was counted out and attempts were made by the referee and others to revive him.
Paramedics were called to the scene and the show was paused before the audience, who had been chanting "Silver, Silver," were asked to leave.
Very sorry to hear of the passing of my friend, the great Mexican Luchadore Silver King. He was always a pleasure to spend time with and wrestle when we were both in WCW in the 90's.— William Regal (@RealKingRegal) 12 May 2019
Show organisers Lucha Libre World announced Barron's death Sunday morning.
"We are sorry to confirm that last night at the Greatest Show of Lucha Libre at Camden's Roundhouse, Cesar Cuauhtemoc Gonzalez Barron (AKA Silver King) suffered what we believe was a cardiac arrest while performing in the show and sadly passed away," a statement from the organisation said.
"We have truly lost one of Lucha Libre's greatest wrestlers and our thoughts and deepest condolences are with Cesar's family and his fans across the world."
In a tweet on Sunday morning, the Roundhouse said: "At this stage the details are still being investigated so we don't have more information we can share. Our thoughts and condolences are with his family, friends and all of the Lucha Libre team."
Barron was a second-generation wrestler whose father was the well-known luchador Dr. Wagner.
He joined WCW in 1997, regularly appearing on the headline show "Monday Nitro" and challenging for the cruiserweight title before he was released in 2000.
Five years later, he played the villain Ramses opposite Black in Nacho Libre, a role he was also fulfilling during his final show.