Miami - The nude assailant who almost killed another man over the weekend by biting his face off was identified on Tuesday by Miami police, who said they are still in the dark about what provoked the izarre and savage attack.

The aggressor, Rudy Eugene, 31, was shot dead by police who said he had devoured almost the entire face of his victim.

The homeless man, who also was naked during the attack, has been identified by Associated Press as Ronald Poppo, 65. Poppo was reportedly in critical condition on Tuesday, with only his goatee intact on his face.

“We are expecting a report from our detectives to give more details to the media. We are also looking for more witnesses to this crime,” a Miami police spokesman said. “The victim remains in critical condition.”

The bloody spectacle unfolded mid-afternoon on Saturday, when police were alerted by the public as the attack was being carried out near Miami's MacArthur Causeway.

Police ordered Eugene to stop the assault, then fatally shot him when he continued to gnaw at the face of his victim.

Television footage and news photos have shown the two men sprawled on the sidewalk side by side, with Poppo barely conscious and covered in blood with up to 75 percent of his face ripped off.

Police initially said the attack could have been provoke by an overdose of a powerful new form of LSD mixed along with “cocaine psychosis.”

Reports however on Tuesday suggested Eugene was likely under the influence of the synthetic stimulant “bath salts” made with the active agent mephedrone, which produces an often aggressive, chaotic experience for users, coupled with intense hallucinations.

Authorities hope that the victim, if he survives, could help explain what precipitated the grisly attack.

“We're hoping that he pulls through, for his well-being, but also so he can tell us what happened,” said Sergeant Javier Ortiz, vice president of the Miami police union. “Only he knows.” - Sapa-AFP, AP