A suspect who allegedly chewed off a 78-year-old man’s ear on a Portland suburb train platform thought the victim was a robot, according to prosecutors.

Police in Gresham, Oregon, responded to a report of a possible stabbing on Cleveland Ave. MAX platform, 1250 NE 8th Street, on Tuesday after 2:15 p.m., where witnesses said they saw a considerable amount of blood.

When Gresham police and a Multnomah County deputy arrived, they witnessed Koryn Daniel Kraemer, 25, allegedly on top of the 78-year-old victim, still attacking him. Kraemer was taken into custody, and the victim was taken to the hospital.

Investigators later confirmed it was not a stabbing but that the victim’s ear and part of his face had been bitten off.

“The injury was so severe that responders could see the victim’s skull,” the Gresham Police Department said in a press release.

When authorities arrested Kraemer, he allegedly gave them a fictitious name of “El Baker,” and he had to be booked into jail under that name until his real identity could be confirmed, police say.

Multnomah County Jail confirmed Kraemer’s identity through fingerprint comparisons and discovered he had recently moved from Georgia to Portland.

During an interview with authorities, Kraemer said that he believed the 78-year-old man was a robot because of how the victim smelled, according to Multnomah County District Attorney’s Office.

“Kraemer further stated that he spit out the flesh of the victim that he had consumed and that the responding law enforcement had saved his life by separating him from ‘the robot,'” the district attorney’s office said in a press release.

Prosecutors noted the suspect also admitted to consuming alcohol, cannabis, and fentanyl pills.

A man who once rented a room to Kraemer told Portland-outlet KGW 8 that the suspect was at-first pleasant to be around when he was not drinking or smoking cannabis. However, the homeowner claimed that Kraemer started mumbling to himself and was causing damage to the home before he was subsequently kicked out.

The homeowner also told KGW 8 that Kraemer said he attended Oberlin College in Ohio, where the school’s athletic website notes that he was a goalkeeper on the men’s soccer team in 2015 and 2016.

Kraemer is facing second-degree assault charges, and prosecutors have requested that he be held in prison without bail.

You can follow Ethan Letkeman on Twitter at @EthanLetkeman.