Beijing Olympic Games

NAIROBI, Kenya (AP)—Kenyan 400-meter runner Elizabeth Muthuka was banned for two years after testing positive for the steroid nandrolone.

Athletics Kenya secretary-general David Okeyo said Wednesday that Muthuka returned a positive test in July after setting a Kenyan record of 50.2 seconds at the national championships. She broke the 24-year-old mark by 3.1 seconds.

Muthuka is the fourth female runner Athletics Kenya has banned for doping in the past five years. Okeyo said all the athletes who failed doping tests had unwittingly used medication containing banned substances.

“But ignorance is no defense,” Okeyo said.