Peruvian police have arrested Jacinto Nicolas Fuentes German, who is suspected of being a leader of Colombia's Urabenos criminal gang.
Peruvian officers detained Fuentes in Lima, after a joint intelligence operation with Colombia, Peru's police chief, Raul Salazar said on Thursday.
Fuentes, known as Don Leo, entered Peru illegally last month with a false passport, they added.
Salazar identified Fuentes as head of the Urabenos criminal gang in Colombia's Bajo Cauca region, which is a traditional stronghold of ex-paramilitaries.
After the illegal Colombian militias disbanded in the middle of the last decade, many of their members formed drug-trafficking bands of which the Urabenos is among the most prominent.
Urabenos has battled other criminal gangs for control of drug trafficking routes out of Colombia, which is the top exporter of US-bound cocaine.