During their retreat, the Dutch forces demolished a bridge crossing the Tjianten River, but did not demolish another crossing further to its west, to Blackburn's chagrin as this restricted the ability for his unit to maneuver against the Japanese advance and forced him into a defensive battle. Leuwiliang had been previously designated as a base for offensive and defensive warfare in West Java in Dutch strategy, and the Japanese invaders were aware of this. Blackforce consisted of roughly 3,000 men—a brigade-sized unit—but roughly half of them were non-combat soldiers such as cooks, medics and drivers. Blackburn organized his men into three battalions—1st battalion mainly consisting of a preexisting 2/3rd Machine Gun Battalion, 2nd mainly made up of the 2/2nd Pioneer Battalion, and a 3rd battalion made up of engineers, soldiers who escaped the defeat in Singapore, and some additional reinforcements. They were also supported by three batteries of the American 2nd Battalion/131st Field Artillery Regiment, the only American ground unit in the Dutch East Indies campaign and was commanded by Lt. Col. Blucher S. Tharp. The brigade was further supported by a squadron of fifteen light tanks from the British 3rd Hussars Regiment. The Pioneer Battalion, the best unit in the Blackforce, was placed in the front line of Leuwiliang's defenses (east bank of the Tjianten River) with two companies defending the road and two in reserves, while the Machine Gun Battalion was stationed in the flanks and in supporting positions. The Nasu Detachment contained two Regiments—the 16th Infantry and the 2nd Reconnaissance—with supporting units including an artillery battalion and a tank squadron. The 16th Infantry Regiment had (before landings) a strength of 2,719 men while the Reconnaissance Regiment had just 439. They employed the Type 97 Te-Ke tankette in the Reconnaissance Regiment. In the afternoon of 3 March, the advance armored car units of the 2nd Reconnaissance Regiment arrived in the vicinity of Leuwiliang, and found the demolished bridge shortly before the Australian defenders on the opposite bank opened fire with machine guns and antitank rifles, destroying the leading vehicles. The Regimental Commander, Noguchi Kin'ichi, deployed his units—two infantry companies forming the front line and two as reserves, and planned to cross the river south of the demolished bridge before launching a surprise night attack on the Australian positions. Blackburn anticipated this flanking maneuver, and stationed the C company from his Machine Gun battalion south of his positions, supported by one of the American artillery batteries.