A body was found Sunday morning in the waters off a beach in Shirley, Suffolk police told News 12 Long Island.
They said the victim appears to be a Black woman in her 20s. There were no obvious signs of trauma.
Police Commissioner Rodney Harrison said there was no obvious link between the unidentified woman and any reported missing persons.
Todd Shusterman, of Shirley, told News 12 Long Island he spotted the body on his morning walk with his dogs and called 911.
"I saw something in the water. At first, I thought it was rocks but then I realized we don't have large rocks that you'd see in the water. So I took a few more steps and then I saw what looked like a body," Shusterman recalled.
Shirley Beach was temporarily closed Sunday morning while investigators were on the scene.