(NEW YORK) -- The FBI has joined the investigation into the shooting death of a Maine man in an apparent case of road-rage on a highway in Pennsylvania. The search for a murder suspect is intensifying with authorities looking for the driver of a pickup truck who police believe shot and killed 28-year-old Timothy Davison of Poland, Maine.
"This was a very extreme case, this was a rarity. And frankly the details of the case are disturbing," Pennsylvania State Police Trooper Adam Reed said.
Police are also investigating if the suspect could have been involved in another case of apparent road-rage.
Davison was traveling along Interstate 81 in Pennsylvania after visiting family for the holidays. Just after 2 a.m. last Saturday, Davison made a frantic call to police, telling a dispatcher that a Ford Ranger-style pickup truck was trying to run him off the road. Davison reported the driver in the other vehicle opened fire, according to police.
The other vehicle then rammed Davison's car, forcing him on to the snowy median, where his car became stranded, according to police. That's when police say the driver of the truck got out of the vehicle and fired several shots. Davison was hit several times and later died from his injuries at a local hospital.
"He was on 911 for the majority of this incident and we are reviewing the tapes to try and see if we can get any information to help us find out what happened," State Trooper Robert Hicks said.
Police fear this wasn't an isolated incident because seven hours before Davison was shot, a black truck pulled up alongside another car and someone inside fired several shots, narrowly missing the driver's head in nearby Monaghan Township, Pa.
Authorities are still investigating whether the two incidents are related.
"We're taking this incident very seriously. We're leaving no stone unturned as far as the investigation is concerned," Hicks said.
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