Santos called Cano's death the "biggest blow" against the Revolutionary Armed Forces of Colombia (FARC) in the group's history.  He urged the leftist rebels to "demobilize" now that their leader is dead.  The president said "violence is not the way."

Images from government television showed the body of the FARC commander without his signature glasses and heavy beard.  But officials say fingerprints proved it was Cano.

Military officials said troops also recovered several computers, memory sticks and cash.

FARC rebels have been at war with the Colombian government since the 1960s.  While the number of FARC rebels has dwindled over the years, analysts estimate the group retains as many as 9,000 fighters.

Newspapers quickly carried word of Cano's death.  Some residents in the capital of Bogota said the FARC leader's death gave them a sense of security.  Others said it was a sign that the country was on the path to a true peace.

Cano, who came from a middle class family and whose real name was Guillermo Saenz Vargas, became the leader of the rebel group in 2008 after the death of its founder, Manuel Marulanda Velez.  He is believed to have joined FARC in the 1970s after studying anthropology at Bogota's National University.

Most of the group's funding comes from cocaine trafficking and extortion, but the leftist rebels are believed to be holding an unknown number of people for ransom or political leverage.

FARC has been designated as a terrorist organization by Colombia, the United States and the European Union.

Some information for this report was provided by AP and Reuters.