Alfonso Cano, the top military commander for the Revolutionary Armed Forces of Colombia or FARC, lost his 10th commander by death or capture in less than a year by Colombian military forces, El Tiempo reported Monday.
Alirio Rojas Bocanegra was killed last Thursday and was chief of security for Cano.
Bocanegra was the replacement for Arquimedes Munoz who was killed in March.
President Juan Manuel Santos said these deaths and arrests of FARC commanders mark an important step toward Cano's eventual capture.
"For every leader they put into power, we take one out," Santos said.
The killing of Magaly Grannobles last July was also a significant loss for Cano, who was responsible for Cano's security.
Cano took control of Colombia's largest and oldest rebel group in 2008 when FARC founder Manuel Marulanda died.