The truck was descending a steep hill on nearby MacFarlan Avenue before it suddenly careened into the park.
An ambulance took the driver to St. Joseph's Regional Medical Center in Paterson.
A paramedic team from St. Joseph's assisted Hawthorne EMTs.
Hawthorne firefighters tended to a crash-related fluid leak and remained on standby at the scene until the vehicle was safely removed by a wrecker.
Boyd A. Loving contributed to this article.
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