The Cape Cod Collegiate Baseball League's Brewster Whitecaps confirmed the deaths on Twitter.
Altobelli coached the team from 2012 to 2014 when his son JJ was a player.
Altobelli's wife Keri and daughter Alyssa, a player on Bryant's basketball team at Mamba Sports Academy, were en route with Bryant for a game when the Sikorsky S-76 crashed in Calabasas, Calif., on Sunday morning.
The Los Angeles County Sheriff’s Office said all nine people on board were believed to have died in the crash, but investigators would not identify any of the victims.
Altobelli was also the longtime head baseball coach for nearly three decades at Orange Coast College.
“John meant so much to not only Orange Coast College, but to baseball,” Orange Coast Athletic Director Jason Kehler said in a statement. “He truly personified what it means to be a baseball coach. The passion that he put into the game, but more importantly his athletes, was second to none - he treated them like family. Our deepest condolences go out to the Altobelli family during this time of tragedy.”
Altobelli made history as the longest-tenured baseball coach the school had ever seen and was in his 24th season as head coach, scoring numerous accolades for the program throughout the years.
Mourners gathered at the OCC dugout Sunday to honor his life and legacy.
“We have lost a member of our OCC family, and our hearts are broken,” OCC President Angelica Suarez said in a statement. “Coach Altobelli was a giant on our campus - a beloved teacher, coach, colleague and friend. This is a tremendous loss for our campus community.”
He was survived by his son JJ and his daughter Alexis, according to the Brewster Whitecaps.