BOGOTA, Colombia -- (AP) -- Colombia's military killed the field marshal and No. 2 commander of the country's main leftist rebel group in bombing raids and combat targeting a major encampment at the edge of the country's eastern plains, authorities announced Thursday.
The death of Jorge Briceno, 57, is a huge setback for the Revolutionary Armed Forces of Colombia, or FARC, which has been reeling from a decade of attacks by the U.S.-backed military.
President Juan Manuel Santos called it "the most crushing blow against the FARC in its entire history'' -- more important than the March 2008 bombing raid across the border with Ecuador that killed FARC foreign minister Raul Reyes or the bloodless rescue in mid-2008 that freed former presidential candidate Ingrid Betancourt and three U.S. contractors without firing a shot.
Santos was defense minister at the time of both those government victories.
Santos told a news conference in New York that at least 20 rebels were killed, including other senior insurgents, in bombing raids that began Monday night and involved at least 30 warplanes and 27 helicopters. Ground combat ensued on Wednesday.
Briceno belonged to the FARC's seven-member ruling Secretariat. The group's main leader, Alfonso Cano, remains at large and is believed to be in the mountains of central Colombia.
Colombian officials say they believe other Secretariat members are hiding out in neighboring Venezuela.
Defense Minister Rodrigo Rivera said the operation that killed Briceno targeted "the mother of all FARC camps," a complex some 300 meters from end to end that included tunnels and a concrete bunker where the slain commander "took refuge."
He said troops, five of whom were wounded, engaged rebels in combat on Wednesday and were only able to confirm Briceno's death on Thursday morning. Rivera said the only government death was an explosives-sniffing dog named Sacha.
The hemisphere's last remaining large rebel army, whose numbers authorities estimate at about 8,000, has been badly weakened over the last decade by a military that has received billions of dollars in U.S. aid, including the formation of the elite commando units that participated in the operation.
Briceno died in the cradle of the FARC, near the town of La Julia in the region known as La Macarena, said Santos.
Alvaro Balcazar, the civilian coordinator of a government counterinsurgency plan in the region, said medical examiners had the body and were checking its fingerprints to confirm Briceno's identity.
Santos said the identity had been confirmed.
"This is the Welcome Operation' that we have been promising the FARC," said Santos, who took office on Aug. 7 after being elected on a promise to continue his predecessor Alvaro Uribe's withering military campaign against the FARC.
President Santos was defense minister from 2006-2009, when Washington's biggest ally in Latin America badly battered the rebels, who suffered record desertions.
The FARC was formed in 1964 and Briceno, like most insurgents from a humble background, was a member for most of his life, joining as a teen and even learning how to read as a rebel.
He became well-known internationally during failed 1999-2002 peace talks in a Switzerland-sized swath of southern Colombia that included the La Macarena region.
Briceno, a swaggering figure with a walrus mustache, would hold court with reporters and top Colombian officials in a safe haven granted for those talks, arriving on rutted dirt roads in a stolen late-model SUV. Photographs of him more recently show a gaunt man who authorities say suffered from diabetes.
The FARC increasingly turned to drug trafficking in the late 1990s, when it was at the height of its military power, as a means of financial support.
It has also used ransom kidnappings and extortion as a revenue source, though less so in recent years as it became increasingly difficult for the insurgents to hide their captives.