Federal police have arrested a former national security agent and onetime movie actor on suspicion he was the triggerman in the 1984 murder of leading newspaper columnist Manuel Buendia, authorities said.

The Mexico City attorney general's office identified the suspect as Juan Rafael Mora Avila, 36, a member of a prominent family of politicians from the neighboring state of Puebla.Jose Antonio Zorrilla Perez, former director of a now-dissolved equivalent of the FBI, was arrested June 13 in Mexico City for allegedly masterminding the murder and is awaiting trial on charges of homicide.

Buendia, whose front-page column in the newspaper Excelsior exposed wrongdoing in high places, was shot to death on May 30, 1984, at the entrance of a parking garage after leaving his office.