A central figure in the assassination last year of Luis Donaldo Colosio, the leading presidential candidate of Mexico's governing party, had previously been a paid informer for the CIA, American intelligence officials say.
The man in question is Fernando de la Sota, a longtime security officer for the Mexican government. De la Sota directed a private security force for the Colosio campaign and was present when Colosio was shot while leaving a rally in Tijuana on March 23, 1994.He worked in secret for the Mexico City station of the CIA from about 1990 until 1992. The agency ended the relationship shortly after he was forced to resign from his last official law enforcement post, U.S. intelligence officials said.
While he is not suspected of direct involvement in the killing, de la Sota was charged in February with making false statements to investigators after he repeatedly changed his story of the assassination and its aftermath. He was released on Feb. 28 after paying a $7,000 bond. Mexican officials said he remained a focus of their investigation.
The presence of an alleged former CIA agent at the assassination, which is as mysterious and murky to Mexicans as the killing of John F. Kennedy is to many Americans, is likely to deepen the sense of political intrigue in Mexico and cause some chagrin for the Clinton administration, which has closely linked itself to the Mexican government.
A spokesman for the Mexican attorney general's office, Juan Ignacio Zavala, said the Mexican authorities were unaware of de la Sota's past connection with the CIA but did not believe that it would be relevant to Colosio case.
Despite the apparent lack of a connection between de la Sota's past CIA service and his presence at the assassination, his personal history, which includes a criminal record, troubles some American intelligence officials.
They said their awareness of such problems was heightened by the recent case of a Guatemalan colonel suspected of involvement in the killings of an American innkeeper and an Guatemalan guerrilla married to a U.S. lawyer.
The CIA has long recruited foreign agents from the ranks of military, intelligence and law enforcement officers, seeking information on rulers, rebels and drug runners. The agency last year began a worldwide review of agents on its payroll, looking for any evidence implicating them in human rights abuses, terrorism or drug trafficking.
CIA officials say they will try to purge suspected wrongdoers from the payroll and scrutinize those who remain.
An agency spokesman, Mark Mansfield, declined to comment on the case.
De la Sota, 45, who is 6 feet tall and weighs about 280 pounds, is known by Mexican officials who have worked with him as El Gordo, or the Fat Man. He worked from 1973 to 1985 for Mexico's Federal Security Directorate, a famously corrupt branch of the Mexican Interior Ministry that has since been disbanded.
After 1985, de la Sota joined an Interior Ministry counterintelligence unit based at Mexico City's international airport. He was jailed for nearly a year on a charge of abusing his authority, a former Mexican official said. Nevertheless, he later served on the presidential military staff, as deputy director for arrests for Mexico City's attorney general and as chief of Mexico City's investigative police in the city's wealthiest borough.