Belorussian Military District
The BMP-1 entered service with the Soviet Army in 1966. The first unit to be equipped was the 1st Motor Rifle (renamed as Armoured) Battalion of the 339th Guards Red Banner Belostok Motor Rifle Regiment of the 120th Guards Rogachev Motor Rifle Division (Belorussian Military District), which tested thirty Ob'yekt 765 IFVs and three experimental Ob'yekt 765s.