The RAF Regiment comes under command of 2 Group, Air Command. Its members are organised into eight regular squadrons, - Nos 1, 2, 15, 26, 27, 34, 51 and 63/Queen's colour Squadron - of which six are field squadrons and two are specialist CBRN (Chemical, Biological, Radiological and Nuclear units under the umbrella of the defence CBRN Wing (No 20 Wing RAF Regiment -see note below), plus four Royal Auxiliary Air Force (RAuxAF) Regiment (RAuxAF Regt) squadrons. These are intended to counter ground-based threats to overseas/deployed RAF assets and, to this end, are trained as mobile infantry to move on foot, or in helicopters and protected mobility vehicles, to defend airfields and landing sites. The large area surrounding airfields (regularly up to 140 km square) means RAF Regiment rifle flights (platoons) often spend long periods of time deployed on the ground deterring and detecting potential attackers. Leaving aside those injured, seriously or otherwise, five RAF Regiment gunners were killed in Iraq (one in a firefight, three, including a member of the RAuxAF, in a single mortar strike, and one in a road traffic incident) and five were killed in Afghanistan (one due to hostile fire, four due to IEDs, including one 51 year old member of the RAuxAF, the oldest member of the British Armed Forces to die in Afghanistan) with an additional man dying in an accident in Cyprus after leaving Afghanistan. Additionally, over the same period, three Military Crosses have been awarded to RAF Regiment members for conspicuous bravery. Four RAF Regiment personnel were killed by the IRA, all in 1988 and 1989 - one killed by hostile fire in Northern Ireland, the rest by snipers or bombs wired to cars in Europe.