"Will this person do it again?" asked Pennsylvania State Police Capt. Steven Junkin in a news conference addressing the death of Timothy Davison, CNN reported Saturday.
"We don't know. We don't want to take that chance," he added.
Davison, 28, was killed last weekend when he apparently forced off Interstate 81 near Antrim Township on the way to Maine and shot multiple times by another driver.
Pennsylvania officials say Davison called 911 several times as he was pursued by a gunman along a 15-mile route between Maryland and Pennsylvania.
Junkin said there was no indication Davison provoked the driver.
Pennsylvania police said they did not believe Davison's death was related to a second shooting that occurred earlier in the day about 50 miles to the northeast or the murder of a state trooper in Kentucky in May, WCSH-TV in Portland, Maine, reported.
Police asked the public and auto body shops in the area to be on the lookout for a Ford Ranger XLT pickup with recent damage.
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