Pablo Escobar’s former chief assassin is a free man. After more than two decades behind bars, Jhon Jairo Velasquez was released from a high-security prison in Colombia Tuesday. The 52-year-old assassin, aka “Popeye,” was discharged early under state protection from Combita prison in Boyaca for studying and “good behavior,” Reuters reported. Velasquez had completed just 22 years of his 30-year sentence, BBC News said.

Velasquez, an Antioquia native, is infamous for working directly alongside the late drug lord during the Medellin cartel’s heyday in the 1980s. The self-confessed killer has been linked to thousands of deaths, including the murder of presidential candidate Luis Carlos Galan in Bogota in 1989. The same year, Velasquez also played a hand in the bombing of an Avianca commercial flight that killed 107 passengers.

Velasquez admitted to killing his own girlfriend in an interview with Semana magazine last year. According to Velasquez, Escobar ordered the killing after discovering that the woman, a former flame, had reached out to the U.S. regarding Escobar’s drug activities as she sought revenge over an unwanted abortion.

Velasquez has been working as a government informant in recent years. He will spend the next four years on probation, BBC News said.