Hawaii's first annual Mixed Martial Arts, Sports and Fitness Expo is expected to bring in more than 10,000 people this weekend.

The expo is a first of its kind for Hawaii's quickly growing mixed martial arts community.

Mixed martial arts, or MMA, is a full-contact combat sport that uses a wide range or martial art disciplines and has been gaining popularity and acceptance nationwide.

Special guests will include UFC lightweight champion and Hilo native BJ Penn, pinup model-turned-boxer Mia St. John and other fighters.

The three-day event begins Friday and will feature exhibition fights, martial arts seminars, fitness competitions and fashion shows.

Producer Javen Guzon said the MMA market in the islands is huge.

"Every other week there's a fight promotion going on," he said. "If it's not on Oahu, then it's on Maui, Kauai or the Big Island."

The expo is just one of a few dedicated to mixed martial arts. Others include the Canadian MMA Expo in Toronto, July's North American MMA Expo in Anaheim, Calif. and August's International Mixed Martial Arts Expo in Long Beach, Calif.