A small plane became tangled with a parachutist and nose-dived into the ground Saturday, the Polk County Sheriff's Office said.

The crash happened around 11 a.m. near South Lakeland Airport, and no one was seriously injured, authorities said.

Sharon L. Trembley, 87, of Mulberry was flying a Cessna 170bB and doing touch-and-go maneuvers, in which a pilot lands and takes off without stopping. At the same time, John Frost, 49, of Gainesville was parachuting from another plane.

About 75 feet above the ground, authorities said, the plane's passenger-side wing became entangled with Frost's parachute lines. The plane nosed downward, and Frost was flung to the ground.

Both men were transported by ambulance to Lakeland Regional Medical Center. Frost was treated and released, while Trembley was held for observation.

The Polk County Sheriff's Office originally gave Trembley's first name as Shannon. Authorities said Sunday his name is Sharon.

The National Transportation Safety Board and Federal Aviation Administration are investigating.