It may not be fun for all the family – well, not in the same way as Monopoly, Trivial Pursuit or Mousetrap, say. The themes of empire building and terrorist-style attacks on opponents would probably provoke an outbreak of spluttering over the Christmas sherry.

It is rare, however, for a board game to be seized by the police. This week that distinction befell War on Terror: The Boardgame; a set was confiscated from climate protesters in Kent.

Following a series of raids on the climate change camp near Kingsnorth power station, officers displayed an array of supposed weapons snatched from demonstrators: knives, chisels, bolt cutters, a throwing star – and a copy of the satirical game, which lampoons Washington's "war on terror".

For the game's creators, Andrew Sheerin and Andy Tompkins, web designers from Cambridge, the inclusion of their toy was a shock.

"When I saw the pictures in the papers I was absolutely baffled," said Mr Sheerin, 32. "I thought: surely no member of the public is going to believe that a board game could be used as a weapon?"

You won't find the game in high street stores; retailers have all declined to stock it. The high street chain Zavvi bought 5,000 sets but strangely withdrew them for sale after one day, citing "poor sales". But since its low-key launch two years ago, War on Terror: The Boardgame has sold 12,000 copies online and through independent stockists, prominently featuring in student bedsits.

Distribution deals have been set up to sell the game in Europe and the United States, where war fatigue has ensured a keener reception than in Britain.

Much like games such as Risk or Diplomacy, War on Terror revolves around players creating empires that compete and wage war against each other for resources and land. The controversial twist allows them to "train" terrorist cells that either attack your enemies or, if you're unlucky, turn against you – like some anti-Western terror groups have done.

There is an "Axis of Evil spinner" intended to parody international diplomacy by randomly deciding which player is designated a terrorist state. That person then has to wear a balaclava (included in the box set) with the word "Evil" stitched on to it.

Kent police said they had confiscated the game because the balaclava "could be used to conceal someone's identity or could be used in the course of a criminal act". Mr Sheerin was unconvinced. "That's absurd," he said. "A beard can conceal someone's identity. Are the police going to start banning beards?"

The game's slanted political overtones were fostered in the build-up to the Iraq war. "When we watched the news there was this endless sense of frustration and disbelief that, despite the mass marches and protests, we were off to war," Mr Sheerin said. "We thought it was a ridiculous process that needed to be ridiculed."

After two years of tinkering Mr Sheerin and Mr Tompkins were ready to find a producer; friends helped raise the £30,000 needed to order the first 5,000 copies from a factory in China.

Most high street stores and toy fairs declined to stock the game; those managers who expressed initial interest were overruled by head office.

"The manager of the local Borders bookshop in Cambridge thought it was a great idea and wanted to trial it," said Mr Sheerin. "A day before it was due to appear, head office said not to stock it. That happened time and time again." Zavvi was on the verge of becoming the first major high street store to stock the game and ordered 5,000 copies last year. But a subsequent decision was made to withdraw it, forcing the store to return the order.

A spokesman for Zavvi said the group had bought the game when it was part of the Virgin Megastore network. "We don't censor our products. The game just wasn't selling."

Rules of the game

The game is for two to six players.

All players begin with fledgling empires on a world map which they expand through the acquisition of land, oil and cities. At any time players can abandon the "pursuit of liberty and oil" in favour of becoming a terror state – or they are designated a terror state by a random "Axis of Evil" spinner.

Empires can also train their own terrorists to target rival empires, although these groups often turn on you later in the game. Terrorists can use special cards such as "suicide bomber", "plane hijack" and "WMDs" to advance themselves. Empires rely on tactics such as "espionage", "regime change" and forcing other empires to sign up to the Kyoto protocol to bankrupt their competitors. "The idea is to encourage the sort of short-term, selfish thinking that led us into war," says Andrew Sheerin, the co-creator of the game.

Belfast Telegraph