The division headed for Puno was commanded by Juan Manuel Pinelo from Ica (one of the sworn in Salta), seconded by the parish priest of the Cusco cathedral, Ildefonso de las Munecas, from Tucumán. They left Cuzco in mid-August and received the support of thousands of indigenous people in the districts of Azángaro and Carabaya. They took the city of Puno without resistance on August 26, after Governor Manuel Químper abandoned it. There 18 Spaniards were captured and executed with clubs and stones. Then they headed towards the garrison that protected the Desaguadero river crossing, where the royalist Joaquín Revuelta was located with 13 artillery pieces and 160 men, who deserted when the Cusqueños arrived on September 11. From there, Pinelo tried to coordinate actions with the head of the republicans of Upper Peru, Juan Antonio Álvarez de Arenales, writing him a letter on September 15 and issuing a proclamation in favor of the government of Buenos Aires:
