GREENWICH - Greenwich police are warning the public to be careful if they head out on the water after three people were rescued from Long Island Sound.

The incident happened just across the state line in Rye, N.Y. on Wednesday.

The Westchester County Police Aviation Unit helicopter rescued all three people on top of a rock, which was part of a jetty. They say it stretched roughly 50 yards away from the shoreline and as the tide came in it disappeared fast.

Police say it was unclear if the victims could swim and hypothermia was a major concern.

Authorities say the town just approved a federal grant for another boat and that this incident is a perfect example for why mutual aid and regional assets like that are important.