UPDATE: Connecticut's Office of the Chief Medical Examiner confirms to E! News that Anthony Hart died of a blunt traumatic head injury.
"The death was classified as an accident," a spokesperson said. "The cause of death was blunt traumatic head injury."
The fellow motocross-racing younger brother of Carey Hart passed away Saturday, after crashing on a Connecticut racetrack during a practice run.
Following the crash at Stafford Motor Speedway, 21-year-old Anthony Hart was airlifted to nearby Hartford Hospital, where he was declared dead a short time later.
According to Connecticut State Troopers, who are awaiting the results of an autopsy expected to be completed later today, Hart lost control of his motorcycle and hit the outer track barricade at roughly 3:30 p.m.
Track officials said the younger brother of Pink's ex, known as Tony in the riding world, was practicing for Doug Henry's New England Grand Prix, which took place Saturday night.
"It is with deep regret that the Stafford Motor Speedway announced that, during a practice session...rider Anthony Hart, age 21, of Henderson, Nev., succumbed to injuries received while participating in the event," the Speedway said in a statement Saturday night.
"The Speedway extends their condolences to the family and friends of Anthony Hart."
Hart, who is said to have suffered fatal head injuries in the crash, was accompanied to the hospital by his father, Tom Hart.
His brother Carey, who has yet to comment on the death, was not present at the time, but was said to have flown in from Sturgis, S.D., after hearing of the accident.