CARMEL, N.Y. – Boaters rescued a 6-year-old girl from a small reservoir north of New York City after finding her clinging to the floating corpse of a family friend who had taken her to the water to cool off, officials said Tuesday.

The cause of the woman’s death was not yet known, and an autopsy was planned, Carmel Police Chief Michael Johnson said. He said she could have drowned or suffered a medical emergency while wading with the girl in Lake Gleneida.

The lake, about 730 yards at its widest, is part of New York City’s water supply system, and swimming there is banned.

“She shouldn’t have been in the lake,” Johnson said.

The woman was identified as Pamela Kaner, 59, of Brewster. Police said she was caring for the girl while the girl’s mother ran an errand.

The girl, whose name was not released, told police that Kaner took her into the water in the early afternoon Monday and was holding her when something went wrong.

The child had no life vest on and was crying as she clung to the woman’s body in the middle of the lake late Monday afternoon, said Carter Strickland, commissioner of the New York City Department of Environmental Protection.

Two men and a woman in a rowboat heard the girl crying for help around 5 p.m. and found her holding on to Kaner’s body, Strickland said.