 Complete the following phrase:  On September 23, 2019, speaking on behalf of the Presidency of Andrés Manuel López Obrador, Interior Secretary Olga Sánchez Cordero apologized to Martha Camacho Loaiza, the wife of a leader of the Liga Comunista 23 de septiembre, who was tortured in 1977. The apology took place in the Centro Cultural Tlatelolco, scene of the 