A Starbucks worker spotted the body with the victim's feet poking out of the rug outside the coffee shop on 145th Street and Frederick Douglass Boulevard in Harlem around 6 a.m.
The employee rushed to the building next door and alerted the doorman, who called 911.
The pair caught on surveillance camera apparently dumped the body of 27-year-old Anthony Lewis on the sidewalk in plain sight and then ditched the Target shopping cart block away.
For a second day, investigators have focused their attention on a first floor apartment on West 147th Street, with detectives and crime scene investigators in and out day.
"I was on my way to school and was coming up the block and saw all the cops and ambulances," witness Christopher Brown said. "It was crazy. I know the Starbucks workers were all standing there in shock."
Lewis was fully clothed and may have had head injuries, investigators said.
"We have some potential wounds to the head, the medical examiner is on scene, and we'll have to wait for an official autopsy," NYPD Chief of Detectives Dermot Shea said. "We'll go from there."
The victim was not carrying identification and was wearing gray sweatpants and a T-shirt, and the body was wrapped in a plastic bag inside the carpet.
The medical examiner has not yet determined the cause of death.
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