 On 26 August 1975, 26-year-old Fernando Haymal was killed by fellow Montoneros for allegedly cooperating with government forces.The Montoneros' leadership was keen to learn from the ERP's "Compañía de Monte Ramón Rosa Jiménez" operating in the province of Tucumán.In 1975 they sent "observers" to spend a few months with the ERP platoons operating against the 5th Infantry Brigade, then consisting of the 19th, 20th and 29th Mountain Infantry Regiments.