ROYALTON, Vt. (AP) — A veteran Vermont State Police trooper was traveling between 79 mph and 86 mph (127.14 kph and 138.40 kph) before his cruiser crashed into an unoccupied fire truck at the scene of another crash on Interstate 89 in March, according to the crash report.

Vermont State Police Cpl. Eric Vitali, who state police said was traveling to first-aid training, was seriously injured in the Royalton crash and was airlifted to Dartmouth Hitchcock Medical Center. He is receiving treatment for a traumatic brain injury.

The fire truck with its emergency lights activated was parked in the northbound passing lane to direct traffic to merge to the right lane when it was hit from behind, according to the crash report provided by the Vermont Department of Motor Vehicles on Thursday. Three flares had been placed behind the truck, the report stated.

The cause of the crash remains under investigation. It’s unlikely that the trooper fell asleep or lost consciousness due to the braking and steering data, the report states. Cell phone records from Vitali’s personal cell phone showed no user activity before the crash. His damaged cell phone was being sent to the National Computer Forensics Institute’s lab for analysis, according to the report.

Vitali has been a member of the Vermont State Police for 19 years.