Federal Bureau of Investigation
GTA III — GTA Vice City Stories
FBI Agents wear black suits with dark glasses and blue jackets with "FBI" printed on the back in nearly all of the GTA III era games (Excluding GTA III itself and San Andreas.). In Grand Theft Auto: Vice City Stories they wear black vests over gray t-shirts with "FBI" printed on the back. The FIB agents are well armed in all appearances, and their vehicles are generally extremely fast. The FBI comes four agents in each car, and since they are well armed and very accurate, they will kill the player extremely quick if they have an open range. They carry MP5 in all of the GTA III era games except for Grand Theft Auto III where this weapon is unavailable and instead they carry AK-47's and will also drop pistols if killed.
In GTA IV, the agency is known as the Federal Investigation Bureau (FIB), presumably to avoid conflict with the real-life FBI. The name is also a play on words, since fib is a synonym of lie.
As the wanted level system changed in GTA IV, they now appear at four stars, sometimes along with NOOSE to assist the LCPD, and more heavily at five and six, and will expertly drive and doggedly follow the player. They now drive FIB Buffalos with four agents to a car and will either shoot at the player out their windows or try to spin the player out if the player is in a car. Agents with their SMGs can make short work of a player's getaway vehicle if he/she doesn't outrun or take out the Buffalo(es) quickly. On foot, agents are typically armed with Carbine Rifles, although some agents carry Pump Shotguns and SMGs instead. Additionally in The Ballad of Gay Tony, agents carry the Automatic Shotgun in place of the Pump Shotgun and the Assault SMG as a supplement to the Carbine Rifle and standard SMG. FIB agents appear to be more accurate than NOOSE's Tactical Response Unit; however, FIB agents are more susceptible to return fire, making them more likely to drop their primary weapons when shot.
They use different types of uniforms. Some agents wear random clothes with black jackets with "FIB" printed in black letters on their sleeves. Other agents wear random clothes with their distinctive blue track jackets with "FIB" printed in yellow letters in the back. Other agents wear black suit pants with a white shirt and a black combat vest reading "FIB" on the back. All agents carry their FIB badges on the neck. In GTA IV, the player, when he/she reaches a certain level, can have a "FIB" hat on his/her multiplayer character.
- DGSE, the French equivalent.