Carlos Rodriguez, 27, fled after the 8:40 a.m. incident on Sunday, Aug. 28, at the Knights Inn off Route 46, Police Chief Robert Chinchar said.
Both had been living together there the past several years, he said.
The victim sustained two small puncture wounds in the back of the neck from a steak knife for which he didn't require hospitalization, the chief said.
South Hackensack police issued an alert to surrounding towns while searching for Rodriguez.
He shouldn't be difficult to spot.
Rodriguez is 5-foot-11 and roughly 300 pounds, with long brown hair and a long beard. He was wearing blue sweatpants and a dark-colored t-shirt.
He's also missing teeth and has two black eyes that authorities said he received when he was assaulted earlier this month.
Although he wasn't believed to be armed, authorities urged caution because of the danger they said that Rodriguez poses to himself and others.
ANYONE who sees Rodriguez, or knows where to find him, is asked to contact South Hackensack police: (201) 440-0042.
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