The blaze apparently broke out in the kitchen at Rare Steakhouse on Main Street around 3:30 a.m.
Firefighters had it knocked down in under 45 minutes. Fire officials declared it under control around 4:50 a.m.
No injuries were reported.
An investigation to determine the cause was continuing, Passaic County Prosecutor Camelia M. Valdes, Little Falls Fire Chief Jack Sweezy Jr. and Little Falls Police Chief Steve Post said in a joint release.
They asked that anyone with information that could help the investigation call the prosecutor’s tips line at 1-877-370-PCPO or email tips@passaiccountynj.org or contact Little Falls police: (973) 256-0200.
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