Arriving officers found two people yelling on the roof of a two-family home at 127 River Road in Raritan Township, just before 10:45 p.m., police said in a news release.
"Utilizing their patrol vehicle, officers were able to safely assist the two adult residents off of the roof," Raritan Police Chief Alfred Payne said.
Responders found flames coming from the second floor of the home, and a total of four people were evacuated, police said.
Raritan firefighters put out the blaze, which was under investigation by township police, the township fire marshal, and the Hunterdon County Prosecutor's Office.
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