Jonathan Rodriguez, 21, is facing murder charges in the death of 65-year-old Richard Hamlet.
Police say Rodriguez, along with 18-year-old Ayame Stamoulis and a possible third suspect, tortured Hamlet before throwing him out of his apartment window.
Stamoulis is also facing murder charges. She was taken into custody on Thursday evening.
Police said Rodriguez and Stamoulis, along with another man, broke into victim Richard Hamlet's apartment in what initially appears to have been a burglary.
When they unexpectedly encountered Hamlet, police say the three beat him, forced him to drink a caustic liquid and choked him.
They then wrapped his dead body in a plastic bag and threw it off the building, landing on the roof of the adjacent McDonald's.
Investigators responded to a call early last Wednesday and found the body partially wrapped in a plastic bag with a U-Haul blanket thrown over it.
The McDonald's closed at East 149 St. next to Lincoln Hospital as customers coming for a meal learned the news.
"That's crazy," Ronald Simmons said. "I live down the block, for this to happen!"
"This is sad this is happening aside from all the bad things already happening, we should be helping each other not killing each other," Madeline Cancel said.
Crews carefully removed the remains.
Investigators could be seen with bags of evidence, placing them into the crime scene unit.
A maintenance worker apparently found the man's body and called police.
MORE: Ex-personal assistant arrested in tech CEO Fahim Saleh's grisly murder
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