From April–October 2001, a composite engineer troop was deployed to support the 4 RAR Battalion Group in East Timor and undertook a wide variety of construction and combat engineering tasks along the border between East and West Timor. During November 2003 – June 2004, 2 CER supported the 6 RAR Battalion Group (AUSBATT IX) in East Timor. 2 CER subsequently led an independent Company Group in support of a multi-national United Nations Security Force as part of Operation SPIRE during the period December 2004 – June 2005. This force conducted a wide variety of support engineering and combat service support tasks in support of other United Nations forces deployed to the country. 2 CER elements returned to Timor Leste in the &lt;a href="8th/9th%20Battalion%2C%20Royal%20Australian%20Regiment"&gt;8/9 RAR&lt;/a&gt; Timor-Leste Battle Group from January– October 2010, as part of Operation ASTUTE.