MIAMI -

Two people were seriously injured on Biscayne Bay when someone crashed into their boat and took off late Saturday night, Miami Fire Rescue said.

At around 11 p.m. Saturday, a man and a woman were trying to get from Nixon Beach, where they had spent the day at the sand bar, to Dinner Key Marina on their small Boston Whaler, according to fire officials. All of a sudden, another boat crashed into theirs, knocking the man unconscious.

In a frantic 911 call, the woman said her boyfriend was bleeding, their life jackets were jammed after the collision and the boat was taking on water. It was difficult for her to tell the operator exactly where they were in the dark waters.

Two rescue crews in helicopters and three agencies searching by boat went out on the water to look for the couple. After nearly an hour, choppers spotted the couple.

On Sunday evening, the man was in serious condition and the woman was in stable condition.

Anyone with information on the boat that left the scene is asked to call police.