"The defendant wanted to try eating at least 10 people in the future," an investigative committee in the Russian Arctic city said Monday.
The 21-year-old man, who allegedly confessed to the crime, had become acquainted with the victim through the Internet, investigators believe, RIA Novosti reported.
"According to preliminary information, one of them was seeking a sexual partner," Murmansk Investigation Committee Chief Fyodor Bludenov said. "The accused explained later that such people are not open, and they prefer to hide their contacts."
In a statement, the Investigation Committee said, "The accused stabbed the man a few times, and after having assured himself that the man was dead, he cut up his body and ate him."
The mother of the victim, who was born in 1959, contacted police in mid-August and investigators checked out his contacts, which led to the suspect.
The suspect could be sentenced to up to 15 years in prison if found guilty, but will undergo a psychiatric exam first to determine whether he is fit to stand trial, RIA Novosti said.
RIA Novosti did not identify the cannibal or the victim.