Now here’s something that doesn't happen every day: a SWAT team raided the Budapest set of Marc Forster’s big-budget zombie pic World War Z earlier today and seized a number of weapons that were being used in the film. Police confiscated 85 fully-functional weapons (read: not prop guns) from a warehouse that was being used by the production. Most of the weapons were of the automatic, military-style assault variety which is a very big no-no to transport internationally without authorization. Hit the jump for the full story, including star Brad Pitt’s reaction.

Apparently the paperwork for the guns claimed that they were non-fuctional, when in fact they were very much real. The fault lies with the production company’s employees who transported the weapons without approval from Hungary's Anti-Terrorism Unit.

Sources tell Us Weekly (via Vulture) that Pitt is “furious.” The film is reportedly already over budget and over schedule, and this snafu has thrown quite a wrench into the production (guns are highly necessary when fighting a zombie army). In addition to starring, Pitt is also a producer on the film so one assumes this is causing a bit of a headache. Witnesses are currently being interrogated and an investigation is underway.

The film centers on a United Nations employee who travels the world in a race against time to stop the zombie pandemic from becoming all-emcompassing. In addition to Pitt, the adaptation of Max Brooks’ novel stars Anthony Mackie, Matthew Fox, Mireille Enos, James Badge Dale, and Bryan Cranston. World War Z opens December 21st, 2012.