GYUMRI, Armenia -- A Russian soldier was stabbed to death in the northern city of Gyumri, where Moscow maintains a garrison and which was the site of a grisly mass slaying by a Russian serviceman in 2015 that triggered widespread outrage in the ex-Soviet republic.
Law enforcement officials said the body of the soldier, identified by prosecutors as 21-year-old Dmitry Yalpayev, was discovered with stab wounds to the neck on April 22 near a shop in Gyumri, Armenia's second-largest city.
Russia's state-owned TASS news agency cited the Russian Defense Ministry's Southern Military District as confirming that a contract soldier serving at the 102nd Military Base, where some 3,000 Russian servicemen are stationed, was stabbed to death at around 4 p.m. local time.
The Armenian Prosecutor-General's Office said a 20-year-old man had been detained as a suspect in the slaying and that a murder investigation was under way.
Authorities did not release the suspect's name.
Armenia's federal Investigative Committee said in a statement later on April 22, however, that "a preliminary investigation has established that the suspect has certain problems with mental health."
The statement said the suspect was discharged from the military last month due to "certain mental disorders" and that he had undergone psychiatric evaluation during his service due to several incidents of self-mutilation.
"Necessary investigative actions are being conducted with his participation," the Investigative Committee said.
Russia’s Southern Military District said in its statement that it was working together with local law enforcement agencies in the investigation.
It added that preliminary indications suggest the killing stemmed from an argument involving the two men.
Gyumri was the site of the horrific slaying of a family of seven, including a 6-month-old boy, by a Russian soldier in January 2015.
The case led to mass protests in Gyumri and Yerevan against Russia's military presence in the country and to calls for the trial to be heard by Armenian judges instead of Russian military judges.
The Russian judges sentenced Valery Permyakov to 10 years in a maximum-security prison in that criminal case. He was then transferred into the custody of Armenia, where he was convicted and sentenced to life in prison.