Six people were injured including the three hospitalized, the other trio declined treatment, Hackensack Fire Captain Justin Derevyanik said.
At 8:13 p.m., an unknown odor that irritated residents' throats brought a Bergen County HazMat Unit, Hackensack Fire Department and Teaneck FAST team to the third floor of the 2000 building of the Avalon Hackensack at Riverside apartments, the captain said.
Bergen County HazMat cleared the Hackensack Avenue building just before 10 p.m., allowing the nearly 100 occupants back inside while the source of the odor remained undetermined, Derevyanik said.
The firefighter was transported to Hackensack University Medical Center and the residents were transported to Englewood Medical Center, the captain said.
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