The FBI reportedly spied and gathered intel on Gabriel García Márquez for 24 years.

The surveillance, which remained private until now and contained 137 pages of documents, began in 1961 when the Colombian author lived for at the Hotel Webster in Manhattan alongside his wife and their oldest son, Rodrigo Garcia. The Washington Post requested and declassified the agency's documents and published them on Sept. 4.

At the time, García Márquez traveled to the U.S. to work as a journalist for the Cuban news agency Prensa Latina. He later won a Nobel Prize award in literature and became a well-known leftist and friend of Cuban dictator Fidel Castro, the news outlet added.

The reason behind FBI's surveillance of García Márquez was unclear. The bureau did not release an additional 133 pages about the "Love in the Time of Cholera" author, but the records gave no sign that the FBI opened a criminal investigation on him.

One of the entries in the documents was dated Feb. 8, 1961, which showed an order from FBI Director J. Edgar Hoover that the bureau be immediately informed if the writer "enters the U.S. for any purpose," Washington Post wrote. Another entry on the same date emphasized García Márquez's link to Prensa Latina, which, according to FBI, "included a number of communists and procommunists," the mews outlet added.

Agents also took note that García Márquez, then 33, was not credible covering a Cuban man's murder trial in 1961. As quoted by The Washington Post, the report reads: "García Márquez had extreme difficulty with the English language. As a result García Márquez appeared to be in a poor position to cover the events of the trial."

García Márquez's elder son, Rodrigo, told The Washington Post that he and his family were clueless about FBI's surveillance on the writer. But he said that the news was not surprising to him, recounting how his father "more than once told of a time in 1960 or 1961 that he finished his workday and realized he was being followed on his walk home by two men who appeared to communicate by whistling," the news outlet added. Back then, they assumed that the spies were from the CIA or a Cuban faction.

García Márquez died aged 87 on April 17, 2014 at his home in Mexico City, Fox News Latino wrote. In August, it was reported that his cremated remains are going in his homeland of Colombia to be displayed at an exhibit in the Caribbean city of Cartagena, The Guardian noted.