As Freedom's commandant he is second in command to, and close friend of, Chekhov. He also is in charge of monitoring and maintaining all the patrols and movements Freedom made, which made it easy for him to sell them out. When Scar arrives at the Freedom base in the Dark Valley, he meets with commandant Lingov in order to get access to Chekhov. The annoyed Lingov first sends the player on a quest to kill a Psy dog which has been terrorizing the base, then another quest which involves delivering ammo to a Freedom camp. Upon arriving at the camp, Scar finds all its inhabitants dead. He also locates a PDA with a recorded dialogue revealing Lingov's involvement with the mercenaries who have been attacking Freedom. Before he can be detained, the commandant flees from the base and meets up with mercenaries at a farmstead. There, he is subsequently killed by the very same mercenaries, presumably for selling false information to them. Lingov's own PDA is then used by Chekhov to gain information about mercenary activities in the Dark Valley.
Lingov's actions were succeeded by another Freedom member named Pavlik in Shadow of Chernobyl where he also sold Freedom out to the Mercenaries, and again he and the mercenaries are terminated.
Strangely after Lingov's death, Ashot and Yar never argue again...much to the dismay of many. The two may have been doing it specifically to annoy Lingov, however, as he interrupts each argument by telling them both to shut up.
In his second mission to send ammo to the camp, you actually get to keep the ammo Ashot gave you since the ones who were suppose to receive it are dead. You get 4 boxes of 5.56x45mm AP rounds and 3 RGD-5 Grenades
In some of the translations, like the original Russian one, he is called just the Commandant.
According to the radio chatter of Freedom members when you find his body they will say that mercenaries found Lingov a nice place on the treee. Looks like mercenaries has hanged him.