As part of the British contribution (codenamed Operation Veritas) to the 2001 invasion of Afghanistan at the start of the War in Afghanistan, the RAF provided support to the United States by operating air-to-air refuelling tankers and reconnaissance aircraft as well as proving the use of its bases. Chinook helicopters have provided airlift support to coalition forces. In late 2004, as part of Operation Herrick, RAF Harriers were based at Kandahar Airfield in Afghanistan, operating in the close air support role against the Taliban. The Harriers were replaced by an equivalent force of Tornados GR4 in spring 2009. From March to May 2002, No. 39 Squadron took part in Operation Ramson, looking for terrorist threats in Somalia.