Police are investigating how the remains of an adult woman ended up inside the Borinquen Plaza NYCHA building in Williamsburg.

According to police, officers responded to a 911 call just before 9:40 a.m. Sunday for an unconscious person inside 330 Bushwick Ave. When they went into the basement, they found human remains.

Investigators say a New York City Housing Authority worker who made the discovery.

Throughout the day, detectives and crime scene units went in and out of the building carrying bags of evidence as they continued their investigation.

Residents say the discovery has been deeply disturbing.

“From the window, all I saw was a black bag. A black garbage bag. That’s it. I didn’t know it was a body at first,” one resident said.

Another resident added, “How could you put a young lady in a bag? We’re human beings. We’re not garbage.”

Police say the woman has not been identified, and there have been no arrests. The investigation remains active.

The medical examiner is expected to determine the cause of death, which could also help investigators learn more about who the woman was and how she ended up inside the building.

Anyone with information is urged to contact police.