NEWPORT, R.I. (CBS/AP) – Investigators are trying to learn more about a bizarre incident off the coast of Rhode Island. A woman said she fell off a sailboat and her husband didn’t know she had been overboard for hours in Narragansett Bay.

The U.S. Coast Guard says the woman said she fell off her husband’s 39-foot sailboat sometime Friday afternoon as they were sailing from Newport to East Greenwich.

Narragansett Bay. (WPRI-TV)

The woman, who authorities haven’t identified, was found on Prudence Island at around 4 a.m. Saturday by a passing boater who heard her cries for help. The Providence Journal reports the woman had mild hypothermia but refused treatment.

Her husband was found around 2 a.m. in Warwick after he ran his sailboat aground. The man told local police he thought his wife was below deck sleeping and didn’t realize she was missing.

“It was pretty challenging because she could have been anywhere. She could have swam to another side of the bay or another buoy or another beach. She could have been anywhere” Petty Officer Sam Van Lent told WPRI-TV.

No other information is available at this point in the investigation.

(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)