"This is a tragic day for Australia, and for the Australian defense force," Prime Minister Kevin Rudd said in a statement to Parliament. "We know our mission in Afghanistan is hard, but this mission is critical for our common security."
4 NATO troops die in Afghan helicopter crash →
He said he would contest the next election and continue to serve the government "in any manner in which I can be of assistance."
Australia gets its 1st female PM as Rudd ousted →