The body of the 25-year-old victim was found on the floor. He'd been beaten with a blunt object, authorities told Daily Voice.
"There was a lot of blood throughout the place," one responder said after city police found the body in the MacArthur Avenue apartment around 10:30 p.m. Saturday and alerted the Bergen County Prosecutor's Office.
Nearly 6½ hours earlier, the victim's 55-year-old roommate stepped in front of an NJ Transit train and was killed in an apparent suicide near the Hobart Place grade crossing, roughly a half-mile from their home, they said.
Next-of-kin notifications were still being made Sunday, so both men temporarily remained unidentified.
The man killed by the train was carrying an Ecuadoran passport, authorities said.
"We haven't determined whether either or both were legally or illegally," one said.
Investigators also were looking for a woman who apparently lived with both men, although they don't believe she was involved in the slaying.
Any murder-suicide determinations must be made by the Bergen County Medical Examiner, who will be conducted autopsies on Monday, they said.
Service on the Bergen County Line to Warwick, NY was suspended following the 3:50 p.m. train death on Saturday.
The #1873 train, which left Hoboken at 3:17 p.m., struck the as-yet unidentified man at 4:09 p.m. near the Hobart Place grade crossing, NJ Transit spokesman Nathan Rudy said.
None of the 150 customers of any crew members was injured, Rudy said.
A follow train was picking them up, he said.
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