ITV is apologising after it was revealed Tuesday that a documentary about the Irish Republican Army mistakenly used footage from a video game, which was claimed to be IRA video from 1988.

"Exposure: Gaddafi and the IRA" used footage showing troops shooting down a British helicopter, but the film was actually from the military video game Arma 2.

An ITV spokesperson said Tuesday evening: "The events featured in 'Exposure: Gaddafi and the IRA' were genuine, but it would appear that during the editing process the correct clip of the 1988 incident was not selected and other footage was mistakenly included in the film by producers. This was an unfortunate case of human error for which we apologise."

The hourlong documentary, produced by ITV Studios, has been removed from the broadcaster's online catch-up service.

The footage from Arma 2, released in 2009 and set in a post-apocalypse Eastern Europe, was narrated over in the documentary by actor Paul McGann: "It may have been a lucky hit, but for the army and crew, once was enough. No one died in this attack but there were many other deadly arms to fear."

A spokesperson for game developer Bohemia Interactive said: "We've had requests in the past to use Arma 2 footage for scenes in a documentary and the request was turned down because of the possibility it showed Arma 2/Bohemia Interactive in a negative way."