Troopers responding to a call Monday of an erratically driven Ford pickup pulled it over on the eastbound side of Route 78 in Readington (Hunterdon County) around 1:30 p.m., Trooper Charles Marchan said.
They found the driver DWI and carrying heroin, he said.
Suddenly, passenger Christopher Treadwell of Pennsylvania got behind the wheel and took off, Marchan said.
Treadwell, 30, crashed the pickup into another car near Pleasant Grove Road in Washington Township (Morris County), then hopped into a residential pool about an hour later, he said.
A passenger in the car that was struck was airlifted to an area hospital with serious injuries, Marchan said.
Treadwell was charged with vehicular assault, drug possession, among other charges, and sent to the Hunterdon County Jail.
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