MIAMI -- Authorities may never know why a Florida man viciously attacked and chewed on the face of an older homeless man in Miami after lab tests failed to find components of "bath salts" in the system of the assailant, who was killed by police.
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The medical examiner says the tests detected only marijuana in the system of the attacker, ruling out other street drugs that some had speculated Rudy Eugene might have taken.
Lab results also didn't find alcohol or prescription drugs.
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Surveillance video captured 65-year-old Ronald Poppo being attacked by Eugene on May 26. A police officer shot and killed Eugene, who bit into Poppo's face in broad daylight alongside a busy highway. Police have not released a motive for the attack.
Poppo has undergone several surgeries and remains hospitalized.
Associated Press