Adam Johnson, a former NHL forward, has died after his neck was cut by another player's skate during a game Saturday in Sheffield, England.

The fatal collision — which Johnson's team called a "freak accident" — occurred midway through the second period of an Elite Ice Hockey League game between Johnson's Nottingham Panthers and the Sheffield Steelers. Video footage appeared to show an opposing player's skate strike Johnson in the neck, a terrifying scene that prompted officials to empty the arena as medical personnel raced to respond.

Johnson was taken to a local hospital and later pronounced dead, the South Yorkshire Police said. He was 29.

"The Nottingham Panthers are truly devastated to announce that Adam Johnson has tragically passed away following a freak accident at the game in Sheffield last night," the team said in a statement on Sunday. "Adam, our number 47, was not only an outstanding ice hockey player, but also a great teammate and an incredible person with his whole life ahead of him. The Club will dearly miss him and will never ever forget him."

In a statement, the South Yorkshire Police said it had opened an investigation into Johnson's death, and encouraged the public "to avoid speculation regarding the incident."

Johnson was in his first season with the Nottingham Panthers, after spending parts of two seasons with the NHL's Pittsburgh Penguins, followed by a stint in Sweden with the Malmo Redhawks.

A Hibbing, Minn., native, Johnson previously was the assistant captain of the hockey team at the University of Minnesota Duluth. In the 2016-17 season, he ranked second on the team in goals, points and shots.

He also helped lead the team to a NCAA West Regional win and a National Collegiate Hockey Conference Frozen Faceoff championship, and was selected to the NCHC All-Academic Team twice.

"We are deeply devastated to learn last evening of the passing of Adam Johnson," the university said in a statement. "Adam was loved and admired by his teammates, coaches, and staff. As talented as he was on the ice, he was even a better person. Adam remained connected to the program, and for our time with him we are eternally grateful. Adam, we love you, we will miss you."

He left the school early to go pro, and played for the Pittsburgh Penguins in 13 games between 2018 and 2020.

"It was a privilege to be his coach...I remember his first game and his first goal in Minnesota. He was a great kid, a great player. And boy, he could really skate," Penguins coach Mike Sullivan said.

Former Penguins teammate Sidney Crosby, gave his condolences and also recalled being there when Johnson scored his first goal.

"To see him score in his home state was pretty cool," Crosby said. "And just the way he skated. There's some guys that, when you get out there with them, they can just flat out fly. He was one of them."

Penguins player Pierre-Olivier Joseph spoke about playing tennis with Johnson, and what a good player he was.

"I think just the way he carried himself, just a happy person in general - we're sure going to miss him," Joseph said.

England's Elite Ice Hockey League, the National Hockey League and other NHL teams also commemorated Johnson.

"The thoughts and condolences of everyone connected with the EIHL are with Adam's family, friends and team mates at this incredibly sad and difficult time," the league said. "We would also ask everyone to respect the privacy of Adam's family at this time."

The EIHL also postponed all games that were scheduled for Sunday.

The NHL said in a statement it was mourning his death. "Our prayers and deepest condolences go to his family, friends and teammates," the league said.

Incidents similar to Johnson's have happened in hockey before. Last year, Teddy Balkind, a high school sophomore in Connecticut, died after his neck was cut in a collision. In 1989, Clint Malarchuk of the Buffalo Sabres had his neck cut during a game against the St. Louis Blues, but survived.

The English Ice Hockey Association has already said neck guards, which are usually recommended for hockey beginners, would now be mandatory for its players after Dec. 31. The association oversees all levels of hockey in England that are below the elite division in which Johnson had been playing. But it said its "strong recommendation" was for players at all levels to begin to wear neck guards.

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