Protected by a sandbag bunker, Anatoli Seryak peers down the barrel of his rifle, scanning passing cars in the Lithuanian capital of Vilnius for drive-by snipers. He is one of two men on forward sentry duty for OMON, a paramilitary unit of the Soviet Interior Ministry. Nearby, an armored personnel carrier stands guard in front of the unit's fortified headquarters. Two more sentries pace the roof. "If they try anything, there won't be a problem," says Seryak, 33, his trademark black beret tilted high on his forehead. "We're always ready to fight."
The OMON base was the Lithuanian police academy until...