Brigadier General Gonzalo Briceno Zevallos from Peru was appointed as UNDOF's first commander. On 3 June 1974, he arrived at the headquarters of the UNTSO ISMAC House in Damascus and assumed operational command of 90 UNTSO observers detailed to UNDOF. The first phase of the operation was manning the observation posts. The UNTSO observers were transferred to UNDOF, and were joined by advanced parties from both Austria and Peru on 3 June, with Canadian and Polish personnel transferred from UNEF II to the UNDOF Area of Responsibility.