The boy, who was a rear passenger in a 2011 Mazda 3 driven by his grandmother, 66-year-old Hagerstown resident Lorraine O'Neill, was pronounced dead at the scene by emergency personnel following the crash, police say.
Troopers from the Glen Burnie Barrack responded shortly before 7:30 p.m. to the scene on I-97, north of MD Route 32, where the crash was reported.
Preliminary investigations revealed that the child opened the rear window of the Mazda while it was traveling northbound and fell out of the car, landing in the roadway.
Moments later, he was struck by an oncoming vehicle, described as a 2016-2019 Honda Civic.
The driver of the Honda fled the scene and has not yet been located. Police are now searching for the vehicle, which may have damage to its front left wheel well.
Investigators are asking anyone with information about the crash or the Honda Civic to contact Maryland State Police immediately.
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