BOGOTA: Authorities on Monday arrested the former bodyguard of a Colombian presidential candidate shot to death on a crowded airliner more than two decades ago, charging the policemen with being part of the assassination plot.

Former rebel leader Carlos Pizarro was killed in 1990 when an assailant opened fire on him during a flight.

Jaime Gomez, his state-assigned bodyguard, was hailed at the time as a hero for avoiding a bigger bloodbath by killing the candidate's assailant. But in arrested Gomez, the chief prosecutor's office charged he was in on the plot to get rid of Pizarro and killed the candidate's attacker to keep the gunman silent.

Gomez was still working as a criminal police investigator.

The arrest comes as Colombians re-examine the role of corrupt state agents in several high-profile killings of three presidential candidates and other politicians amid drug-fueled violence two decades ago.