A Russian man was arrested and charged with cannibalism Monday after the partially eaten corpse of three people were found along with the remains of dogs, cats and birds in the city of Arkhangelsk.

The 51-year-old unidentified man stabbed his three friends to death with a knife as they fell asleep. He then dismembered their bodies before eating them. He then placed the remains inside bags and discarded them in a local water body.

In a statement, the Russian investigative committee said though the killings took place between March 2016 and March 2017, it took them a really long time to identify the victims. When two of the victims did not have any relatives, the third one was believed to have moved out of town for work.

“Considering that parts of the corpses were found fragmentary, which, in practice, excluded the possibility of their identification, they were only able to establish their identities thanks to a large number of various complex examinations,” the committee said.

The statement added that “besides cannibalism, the accused regularly killed and ate cats, dogs and other small animals and birds, whose bones were found in the bags mixed up with human bones.”

Meanwhile, the accused underwent a medical examination and was considered to be in a fine state of mind.

Representational image of a handcuffed man. SERGEI SUPINSKY/AFP/Getty Images