Given the extremely horrifying circumstances of the “Miami cannibal” story, one of the questions on everyone’s mind is, “Why?” Why did Rudy Eugene suddenly decide to attack a homeless man and eat his face?

Answers aren’t immediately forthcoming, but Miami police think they’ve pieced together at least a little more of the puzzle after investigating Eugene’s whereabouts earlier on the day of the attack. Using witness accounts and running into a bit of luck, they’ve managed to shed light on what Eugene was doing that afternoon before he changed one man’s life forever and lost his own in the process.

According to Eugene’s girlfriend, he was at her house at 2 a.m. on Saturday morning, rifling through clothes and acting erratic. He left abruptly and drove to a friend’s house across town, where he tried to recruit said friend into going to Miami Beach for Urban Beach Weekend, a huge event in the city for Memorial Day. The friend said he was unable to go because he had to work, and Eugene said he would go on his own. He was at the friend’s house until at least six a.m.

Eugene later parked his car around Tenth Street and was apparently unable to get it started again, so he abandoned it; since it was parked illegally, it was later towed. At this point, there are no witnesses to shed light on Eugene’s whereabouts or how long it took him to reach the causeway; police believe he was walking there in order to get back home, which was three miles away. They later found his driver’s license and clothing strewn between the beach and the site of the attack, which was a key component in their belief that he was high on “bath salts”, a dangerous LSD-like drug that causes internal body temperatures to rise and causes delirium.

By the time he reached a sleeping Robert Poppo, the homeless victim, he was fully nude. Surveillance video caught images of Eugene stripping Poppo’s pants off before he attacked his face–decimating at least 75% of it–which may be a clue that he intended to eat more of his victim than he did. By the time a bicyclist noticed the attack and alerted police, Eugene’s damage was mostly done. He ignored the officer’s cries to get off Poppo and was shot several times before being taken down.

Now, the only two people who could shed any light on the tragedy are unable to. Eugene is dead and Poppo is in critical condition with much of his face missing; it’s not known whether he will survive the attack. The questions that remain are haunting ones, and more importantly, may never be answered. Was Eugene indeed on drugs when he attacked Poppo? In the time between abandoning his car and arriving at the causeway, did he ingest “bath salts” in anticipation of the beach party and lose his mind to an LSD-fueled delirium?

Or was the attack caused by something else?