Two people walking in downtown Chilpancingo, in the Mexican state of Guerrero in September 2015. The office of Mexico's Federal Attorney General (PGR) on July 11, 2018, sent an email to the news website Quadratin summoning one of its reporters, Jorge Octavio Vargas Sandoval, for an interview at its regional office in Chilpancingo. (Reuters/Jorge Dan Lopez)
Two people walking in downtown Chilpancingo, in the Mexican state of Guerrero in September 2015. The office of Mexico's Federal Attorney General (PGR) on July 11, 2018, sent an email to the news website Quadratin summoning one of its reporters, Jorge Octavio Vargas Sandoval, for an interview at its regional office in Chilpancingo. (Reuters/Jorge Dan Lopez)

Mexican federal authorities interview reporter as potential trial witness