State police say the crash occurred around 7:40 a.m. Saturday on Route 524 in Upper Freehold Township. They say the SUV slid off the highway and struck a utility pole and a tree.
The three Millstone Township firefighters in the SUV were taken to a hospital for treatment and were released later Saturday. Two of the men had head and neck injuries, while details on the third man's injuries were not available.
The SUV was owned by the Millstone fire district.
Officials say the firefighters were on their way to a training class at the Mercer County Fire Academy.