Michelle Paola Castillo Siguencia was found lifeless on a bathroom floor of a Hudson Avenue apartment in Weehawken around 6 p.m. Saturday, Hudson County Prosecutor Esther Suarez said.
Joseph Palacios was identified as a suspect while Weehawken police were on the scene, the prosecutor said.
Palacios had barricaded himself in a family member's apartment at 112 33rd St. in Union City and was threatening to harm himself, Suarez said.
The Hudson County SWAT Team responded to the scene, and arrested Palacios just before 10 p.m.
Meanwhile, his girlfriend was pronounced dead just before 6:50 p.m.
Palacios was hospitalized for self-inflicted injuries and charged with murder and weapons offenses.
The cause and manner of Castillo Siguencia's death are pending the findings of the Regional Medical Examiner.
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