It happened around 5 p.m. during a JV game at Brunswick High School in Greenwich.
The student who died, Teddy Balkind, was a sophomore at St. Luke's in New Canaan.
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"Our community is mourning," St. Luke's Head of School Mark Davis said. "Yesterday, we lost a precious young man in a tragic accident. Both St. Luke's School and Brunswick School are in shock as we work to support our students and families. St. Luke's singular focus at this moment is to care for our devastated community. Thank you for your concern and for respecting our need to grieve.
Greenwich police say Balkind fell to the ice during the normal course of the game, and a Brunswick player who was near him was unable to stop.
They collided, and Balkind suffered a severe injury, Brunswick school officials said in a letter sent to alumni Friday.
"During a JV ice hockey game last night against St Luke's, a member of the opposing team's neck was accidentally cut by a skate," the letter read. "All who witnessed the play (from both schools) apparently describe the play as entirely normal and unremarkable in the game of hockey."
The boy was treated by Brunswick medical staff before he was transported to Greenwich Hospital, but "tragically, he did not survive the operation," Brunswick officials said.
Balkind played youth hockey New Canaan Winter Club before high school.
"Last night, the New Canaan Winter Club, along with the broader hockey community lost a beloved teammate, friend and community member," the club said in a statement. "Teddy Balkind skated for the Winter Club throughout his youth hockey career and was known to us all as a hard worker and terrific young hockey player. The Winter Club is heartbroken and we join the worldwide hockey family in grief for this unfortunate accident. As the hockey community does, in the coming days, weeks and months we will rally around the Balkind family in support."
Brunswick officials said they were in touch with St. Luke's and with the family.
"We are devastated; an unimaginable tragedy," Brunswick's Head of School Thomas Philip said. "I have, of course, met with the Head of School at St Luke's and have contacted the boy's family to offer whatever help, support ,or assistance we can during such a challenging time. Please keep all concerned in your prayers."
St. Luke's, which was supposed to be remote Friday, canceled classes.
"I mean it's just heartbreaking," New Canaan resident Caroline Thune said. "It's heartbreaking. It's sad. Makes you realize that every day is precious. We need to try to appreciate everything and everyone, because life is fragile."
Counseling will be available for anyone who needs it, school officials said.
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