From AFP via Yahoo! News:
Rudy Eugene, the man who chewed off most of another man's face in a growling naked frenzy before being shot by police last month, only tested positive for marijuana, the local medical examiner said.
Police ordered Eugene to stop and then shot him dead when he refused. The incident, dubbed the "Zombie Attack," made headlines across the country.
Police had suggested Eugene was under the influence of "bath salts," a synthetic stimulant usually sold in shops selling drug paraphernalia which produces intense hallucinations and sparks erratic, violent behavior.