Yuri was a soldier that Solid Snake encountered during one of his missions for Philanthropy between 2005 and 2007.
At some point, Yuri and another group of soldiers were on board a train, and securing various cars. However, by the time he arrived on Car 1, he was ambushed by Snake, who held his comrade hostage and then shot him in the head. His fellow soldiers proceeded to enter the parked train to investigate his disappearance just as Snake exited and requested for Otacon to supply an exfiltration at his mark, with the train exploding shortly thereafter.
Behind the scenes[]
Yuri was a character in the comic book adaptation of Metal Gear Solid 2: Sons of Liberty, specifically issue #0. Unlike the rest of the comic, he and his story were not included in the Digital Graphic Novel.