By Jeremy McDermott
BBC News, Medellin
El Negro Antonio was seized with eight other rebels
Colombian security forces have clashed with a Marxist rebel group and captured one of its most notorious kidnappers.
Soldiers fought Revolutionary Armed Forces of Colombia (Farc) rebels in the central province of Cundinamarca, killing 10 and capturing another eight.
Among those taken was a leader known by the alias "El Negro Antonio", whom authorities have been seeking for well over a decade.
One soldier was killed in the combat and a kidnap victim rescued.
"El Negro Antonio" is a Farc guerrilla with 33 arrest warrants outstanding against him.
The operation took place in the mountain range of Sumapaz in Cundinamarca province.
It is a severe setback for the Farc, not just because of the number of rebels killed and captured, but because it hinders its plans to reopen a movement corridor into the capital, Bogota.
It was along this corridor that El Negro Antonio used to move kidnap victims out of Bogota and into the rebel-controlled lowland jungles.
Under their new leader Alfonso Cano, the Farc rebels have been seeking to retake the initiative snatched from them over the last five years by the US-backed military.
The rebels are seeking to bring their four-decade-old war back into the cities, particularly Bogota, where their attacks have far greater impact than in the countryside.