No one was hurt in the blaze, which broke out just before 2:30 a.m. in the 400 block of Park Avenue and drew borough firefighters and a Cliffside Park FAST team, with Ridgefield providing mutual aid, Police Chief Martin Kahn told Daily Voice.
The other side of the duplex didn't sustain any fire damage, he said.
The cause hadn't been determined, although responders said they suspected an electrical panel because of where the fire started.
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