MARION COUNTY, Fla. -- A 21-year-old woman was killed when her horse stumbled on a jump at a riding event and crushed her on Saturday.

Eleanor Brennan, 21, of Esmont, Virginia, was attending the 2007 Horse Trials, an international horse event, at the Florida Horse Park, a statement from the Marion County Sheriff's Office said.

Brennan was riding an 11-year-old male named Mister Barnabus. The horse struck a gate during the event, tumbled onto his neck and landed on Brennan, the statement said.

The horse died instantly, and Brennan died a short time later at a hospital, the statement said.

Marion County Fire Rescue spokeswoman Heather Danenhower said Brennan had head and chest injuries.

Tom Warriner, chairman of Florida Horse Park, said event officials plan to review tapes to determine what caused the fall.

Brennan was a British citizen who split time between the United Kingdom and Virginia, the Ocala Star-Banner reported. She was completing in the horse park's three-day event.

Brennan's body was taken to the Leesburg Medical Examiner's Office for an autopsy.

A necropsy of the horse will be conducted at the University of Florida.

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