Published: Sep 06, 2010 6:02 PM EDT
Updated: Sep 06, 2010 3:00 PM EDT

CLEARWATER BEACH, Fla. (AP) - Authorities are investigating how a parasail's tether detached from a boat, injuring a couple from Georgia who were vacationing in Clearwater Beach.

Alejandra White and Shaun Ladd were injured Sunday when the tether between a towboat and passenger harness broke, sending Ladd into the water and White crashing into the beach on a runaway parachute.

White suffered life-threatening injuries after being dragged behind the chute through beach umbrellas and into a post on a volleyball court. She's in critical condition in the hospital. Her fiance, Ladd, was not seriously injured. The two were from the Atlanta area.

The Coast Guard, Clearwater police and other agencies are investigating.