Miami-Dade Police Dept. / AP

This undated booking mug made available by the Miami-Dade Police Dept., shows Rudy Eugene, 31, who was shot and killed by Miami-Dade Police after he refused to stop eating another man's face in Miami, Saturday, May 26, 2012. The victim remains hospitalized in critical condition.

The man who mauled off a homeless man's face over Memorial Day weekend apparently had no human flesh in his stomach, a report shows.

Law-enforcement sources told the Miami Herald an autopsy revealed 31-year-old Rudy Eugene had undigested pills in his stomach but no human flesh. The pills have not yet been identified.

Eugene was fatally shot by an officer after he refused to stop chewing on Ronald Poppo's face along the MacArthur Causeway.

Read the original story on NBCMiami.com

Though officials have speculated bath salts may have sparked Eugene's wild behavior, it remains unknown what prompted the attack.

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Officials told the Herald a preliminary review found marijuana in Eugene's system. Those who knew Eugene said he was known to smoke marijuana but the drug is not known to cause violent spurts.

A source also told the newspaper Eugene did not have his two front teeth but that chunks of flesh were found between his teeth. The source also said pieces of flesh were found on the floor of the scene.

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Officials said the autopsy report would not be released to the public until the investigation into the shooting concludes - a process that could take more than a year.

Poppo, meanwhile, continues in critical condition in the hospital.

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The grisly Miami crime scene where police fatally shot a naked man chewing the face off his victim will soon be a tourist stop.

The Miami “Mystery & Mayhem: Crime Tour” tour given by Miami-Dade College professor Paul George, as part of HistoryMiami tours, will stop on the MacArthur Causeway, the South Florida Business Journal reported.

“Horrible as it was, it is part of our history,” George told the Business Journal. “Currently, our tour takes us over the causeway right past the site, so this fits well.”

George, a history professor at Miami Dade College, runs history tours that also include Al Capone's home and the cemetery where Julia Tuttle, a city founder whose name is on a causeway famed for sheltering homeless sex offenders, is buried, HistoryMiami says. The group did not say when the next crime tour will be.

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Miami attracts around 12.6 million overnight visitors a year, according to the Greater Miami Convention and Visitors Bureau.

Miami-Dade Police Dept. / AP

Rudy Eugene, 31, was shot by Miami-Dade Police after he refused to stop eating another man's face in Miami on May 26.

In Milwaukee, a tour highlighting the haunts of serial killer Jeffrey Dahmer sparked an uproar after Groupon offered discounted tickets to see where he stalked his victims, some of whom he mutilated and cannibalized. The chocolate factory worker was arrested in 1991 and beaten to death in prison in 1994.

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Despite protests by vicitms’ families, the Dahmer tours go on every Saturday, Amanda Morden of operator BAM Marketing and Media told msnbc.com.

“Interest in the tours has come from both national and international tourists as well as professors of history and psychology from universities across the United States,” Morden said.

Among other famed crime tours are the Jack the Ripper Tour in London, The Real Black Dahlia in Los Angeles, the Torso Murder Tour in Cleveland and the self-directed Gangster Walking Tour in St. Paul, Minn., along with mob tours in New York, Las Vegas and Sicily.

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In Miami, an attacker identified as 31-year-old Rudy Eugene walked naked on the sidewalk near the causeway’s Biscayne Boulevard exit May 26 before he encountered his victim, Ronald Poppo, 65. Eugene appears in videos to struggle with Poppo, throwing him on the sidewalk as cars and bicyclists speed past and a Metromover public transit car passes by overhead. About 16 minutes into the attack, an officer appears and fires at Eugene, who police said first growled at the officer before continuing to chew Poppo’s face.

Poppo is reported to be in critical condition in a hospital.

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