But former murder squad Detective Chief Inspector Pete Kirkham believes stun guns have become the weapon of choice for many criminals.

BBC: Stun guns bought via mail order come through UK Customs

There are eight categories of weapon, ranging from automatic hardware and machine guns which are prohibited, to hunting equipment allowed with a hunting permit.

CNN: France: Where fear and taboo control guns more than laws

Even if not directly threatened with a weapon, many students are nonetheless aware of the presence of guns and knives on their campus.

CNN: How to deal with guns in school

After the assassination of President John F Kennedy, the purchase of guns through the mail - which is how Lee Harvey Oswald bought his weapon - was outlawed.

BBC: Why America's gun laws won't change

The Cornwall carries a 4.5 inch MK8 gun, Goal Keeper CIWS close in weapon systems, Sea Wolf anti-missile system, Harpoon missile launchers, two 20mm close range guns, Lynx MK8 helicopter armament, anti-ship missiles, and one of the most sophisticated command and control communications systems on water.

CENTERFORSECURITYPOLICY: Iran needs a reason to fear