Police were trying to determine what caused Thursday crash on Maple Avenue just north of Harristown Road just after 6:30 p.m., Police Chief Dean Ackermann said Monday.
No alcohol or drugs were involved, he said.
The driver was taken to The Valley Hospital with injuries that weren't considered life-threatening, Ackermann said.
A witness who'd been driving behind him told police the southbound vehicle "began to swerve and drove directly into a borough shade tree on the opposite side of the street," the chief said.
"Officers recovered numerous vehicle parts which became dislodged and landed in a nearby parking lot," he said.
Glen Rock firefighters and Volunteer Ambulance Corps members responded along with police, the chief said.
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