In July 1899, as tensions between British and Boer settlers in South Africa grew, Queensland pledged a force of 250 men in the event of war. The Boer War subsequently broke out on 11 October 1899 and over the course of the conflict Queensland contributed the third largest force of all the colonies, consisting of 733 troops provided at State expense and 1,419 at Imperial expense, who served in the Queensland Mounted Infantry and Queensland Imperial Bushmen. Following Federation, a further 736 Queenslanders would serve in Commonwealth units. Troops from the Queensland Mounted Infantry were involved in the first significant Australian action of the war when they took part in an attack on a Boer "laager" at Sunnyside on 1 January 1900, during which they lost two men killed and two wounded.