5 RAR's involvement in Afghanistan began modestly in October 2008 when one of the Battalion's mortar sections deployed with the 7 RAR battle group to conduct operations in Uruzugan Province. The deployment of an infantry-led battle group – at this time known as Mentoring and Reconstruction Task Force Two (MRTF 2) – marked a change away from the engineer-led reconstruction activities begun in 2006 towards a wider range of operations, especially building the capacity of the Afghan National Army. The deployment also marked the first time that a mortar section from the Battalion fired high explosive rounds to support friendly troops in contact since the Vietnam War. A larger commitment followed in September 2010 when, as part of the evolving mission, 5 RAR deployed as Mentoring Task Force Two (MTF-2). The 5 RAR battle group was one of two units that made up the main fighting force of what was effectively a small coalition brigade called Combined Team Uruzgan (CTU). The U.S. 1–2 Stryker Regiment initially served in CTU with 5 RAR until March 2011 when it was replaced by the U.S. 4–70 Armoured Regiment. MTF-2 represented the first time since the 1999 intervention in East Timor that Battalion headquarters, all three rifle companies (B, C and D), and Support Company deployed as a unit. Within Support Company, the mortar platoon, signals platoon and snipers deployed in-role, while reconnaissance and surveillance platoon and anti-armour platoon deployed as infantry rather than as specialist platoons.