During the French blockade of the Río de la Plata Juan Lavalle organized an army in Uruguay, attempting to attack Buenos Aires. His plans were supported by conspiracies in Buenos Aires by former member of the May Association. The most notable member of the conspiration was Ramón Maza, son of the former governor Manuel Vicente Maza, who got military support. As Lavalle was delaying, they developed a new plan: Pedro Castelli and Nicolás Granada would make a revolt at Tapalqué, while the military in the city killed Rosas, Manuel Maza assumed government and allowed Lavalle to take the city. The plot was discovered by the Mazorca, but Rosas thought that Manuel Maza was innocent and carried to the plots of his son, so he urged him to leave the country. He could not: Martínez Fontes, one of the military talked into the complot, revealed it in public. Popular commotion was high, and the people took the streets demanding the execution of the people involved with the complot. Ramón Maza was executed, and his parent was killed in his office by the Mazorca. Nevertheless, Pedro Castelli attempted to make a rebellion in the countryside. The people did not follow him, and he was executed as well.