The Siege is a 1998 thriller directed by Edward Zwick and stars Denzel Washington as FBI Assistant Special Agent-in-Charge Anthony 'Hub' Hubbard, who along with his fellow agents are charged with stopping a continuing series of terrorist attacks that have crippled the city of New York. The film is notable for its depiction of the American reaction to such a terrorist attack on US soil. Though the film was poorly received at the time of its release, it was later regarded as prescient following the tragic events of September 11, 2001. The cast included Annette Bening, Tony Shalhoub, and Bruce Willis, and the film was co-written by Lawrence Wright, who is now better-known as the author of the book The Looming Tower.
The following weapons were used in the film The Siege:
The main protagonist of the film, FBI ASAC (Assistant Special Agent-in-Charge) Anthony 'Hub' Hubbard (Denzel Washington) and several of his fellow FBI agents carry SIG-Sauer P226 pistols as their standard sidearms.
Glock 17
The NYPD officers throughout the movie carry Glock 17 pistols as their sidearms. Some of the FBI and CIA agents also use them.
Beretta 92FS
One weapon used by the Army during their occupation is the Beretta 92FS pistol (standing in for the military M9). One soldier can be seen holding one on Hubbard's decoy, and another is presumably the weapon General Deveraux uses to kill Tariq Husseini (Amro Salama). Also, it's difficult to tell (because of the light), but it appears that the terrorist in the safehouse who collects the pizza box (with flash-bang) also has a Beretta lying on the table.
Smith & Wesson 5904
In the climax of the film, one of the FBI Agents appears to be carrying a Smith & Wesson 5904.
Both the FBI agents and many NYPD officers are seen carrying Remington 870 shotguns fitted with top-folding stocks. One of these shotguns is wielded by Agent Frank Haddad (Tony Shalhoub) during the hostage situation at the school.
Ithaca 37
Another weapon wielded by many of the FBI Agents is the Ithaca 37 riot model. Special Agent Frank Haddad (Tony Shalhoub) carries one of these shotguns during the raid on the CIA safehouse.
Mossberg 500 Cruiser
What appears to be a Mossberg 500 Cruiser is wielded by one of the plainclothes FBI agents conducting the raid on the Redhook chop shop.
Submachine Guns
Colt RO635 9mm SMG
During the opening scene in which a team of American black ops soldiers capture the Sheik, they use Colt RO635 9mm SMGs which appear to be fitted with C-More sights. For some reason, the Colt SMGs sound suppressed when they are fired, even though they clearly do not have sound suppressors attached.
Heckler & Koch MP5A3
During both bus incidents, officers of the NYPD's Emergency Services Unit can be seen carrying Heckler & Koch MP5A3 submachine guns fitted with Surefire forend weaponlights, as per norm with SWAT-issue MP5s. FBI tactical agents can also be seen carrying MP5A3s fitted with laser pointers and red dot sights during the raid on the terrorist safehouse.
Curiously, the FBI's MP5A3s have the "Navy"-style lower receivers and Surefire forearms when they are advancing up the stairs, but when they enter the terrorists' apartment and begin firing at them, the MP5s suddenly have the older-style SEF lower receivers and lack the Surefire forearms. It is likely that the MP5s used prior to entry are airsoft replicas.
Heckler & Koch HK94A3 (mocked-up as MP5A3)
At least one of the MP5A3 submachine guns used by the FBI tactical agents during the safehouse raid is actually a Heckler & Koch HK94A3 carbine mocked up as an MP5A3 (judging by the all-metal lower receiver and lack of barrel lugs).
IMI Uzi
During the hostage situation at the schoolhouse, the terrorist holding hostages can be seen wielding an Uzi as he paces about. Despite having the responding police and FBI personnel out-gunned, he's still easily taken down when Hubbard catches him off guard. One of the terrorists in the safehouse raid is also seen using an Uzi. This is a slight cultural irony, as the Uzi is primarily produced in Israel, and is being used by Arab terrorists.
Rifles / Carbines
Savage 10FP
During the Bus 87 incident, NYPD ESU snipers are briefly seen getting into position with Savage 10FP sniper rifles fitted with Harris bipods.
AKM
When the FBI tactical team raids the terrorist safehouse, one of the terrorists engages the FBI in a shootout using an AKM, though is inevitably taken down, shooting blindly and so rapidly that he hits one of his own comrades who gets in the line of fire. As with most of the AKMs used in Hollywood, this is most likely to be a full-auto conversion of an Egyptian-made Maadi ARM.
M16A2
The M16A2 assault rifle features prominently in the movie; almost every soldier involved in the occupation of Brooklyn is seen carrying one. A notable point in the film is that when Major General William Deveraux (Bruce Willis) is describing what the occupation will entail, he distinctly mentions the "M16A1 assault rifle", though the U.S. military had switched to the M16A2 years prior to the events in the film, and indeed the M16A2s are by far the most common rifles in the movie. It is also possible that many of the prop weapons used in the movie are semi-automatic AR-15A2s, standing in for the M16A2 (since they're never fired).
MGC M16 Replica
It appears that some MGC M16 replica assault rifles are used by the U.S. Army soldiers in the movie. Some may be modified to look like M16A2s by adding A2-style handguards and A1-style birdcage flash hiders, but it's hard to tell.
XM177/CAR-15-type Carbine
Throughout the film, it is possible to see many soldiers carrying XM177 look-a-like carbines. They all have long, bulky flash hiders, which tends to characterize the civilian copies of the XM177, such as the CAR-15 seen below. As such, these probably are semi-automatic CAR-15s (or copies/clones) standing in for the military-spec XM177E2.
Heavy Weapons
M203 Grenade Launcher
Throughout the movie, it is possible to spot an XM177-type carbine fitted with an M203 grenade launcher in the hands of soldiers. It appears to be the exact same prop weapon being reused multiple times in different scenes.
M60 Machine Gun
In several scenes, Humvees and Cadillac-Gage Commando APCs can be seen with M60 machine guns mounted on them, most notably when General Deveraux is giving his press conference about the declaration of martial law and when the Army crashes the FBI's raid on the Redhook chop-shop.
Browning M3 Heavy Machine Gun
When the Army crashes the FBI's raid on the Redhook chop-shop, one of the Commando APCs can be briefly seen with a Browning M3 heavy machine gun on the roof.
GE M134 Minigun
An AH-1 Cobra is seen erroneously with a chin-mounted GE M134 Minigun. This is most likely the same civilian-owned Cobra seen in such films as Hulk and Austin Powers in Goldmember. The use of a Cobra by the Army is rather anachronistic, as they had transitioned to the AH-64 Apache years prior to the events of the film.
Grenades
M26 Hand Grenade
During the raid on the Redhook chop-shop, one of the terrorists inside uses the distraction created by the arrival of the Army to pull an M26 hand grenade, the detonation of which provokes the soldiers outside to open up on the shop with everything they have, and Hubbard and Husseini barely escape the onslaught.