|Jorge Briceno Suarez, right, was allegedly a key player in the rebel group's drug-trafficking operations [AFP]
A senior leader of the rebel Revolutionary Armed Forces of Colombia (Farc) has been killed in an air raid, the Colombian military says.
Jorge Briceno Suarez, also known as Mono Jojoy, headed Farc's military operations in the Macarena region in eastern Colombia.
"The symbol of terrorism in Colombia has fallen," Juan Manuel Santos, Colombia's president, said in New York where he was attending the United Nations General Assembly.
"To the rest of the Farc, we are coming after you, we are not going to let down our guard."
Suarez's death would be the biggest setback to the Farc since mid-2008, when its foreign minister was killed and soldiers rescued 15 hostages including Ingrid Betancourt, the former Colombian presidential candidate.
"To the rest of the Farc, we are coming after you, we are not going to let down our guard"
Juan Manuel Santos,
"This is a major blow [for Farc]," Al Jazeera's Monica Villamizar said.
"There is a 10-man secretariat [consisting of] the top commanders of Farc. The number one commander is called Alfonso Cano and this man known as Mono Jojoy was the second-in-command... He represents the toughest stance that Farc has had militarily."
Villamizar said that "most people in Colombia are talking about it, mostly celebrating what has happened because this country has been haunted by 40 years of civil war because of this rebel group".
Suarez was killed in a military operation involving an air strike by more than 30 aircraft and helicopters followed by a ground offensive. As many as 20 other Farc fighters were reportedly killed in the operation in the Macarena region.
The camp which came under attack on Wednesday was a warren of tunnels including a concrete bunker to protect the Suarez from air strikes, Rodrigo Rivera, Colombia's defense minister, told reporters, describing it as "the mother of all Farc camps".
Farc had stepped up attacks in an attempted show of strength since Santos's government took power in August vowing to pursue a hard line against the rebels and dismissing any possibility of talks with the group unless the rebels cease hostilities and release hostages they are still holding.
Colombian authorities said there were dozens of charges outstanding against Suarez, including murder and kidnapping, and US authorities also had lodged an extradition request against him with the Bogota government.
The US state department, which had been offering a reward of up to $5m for information leading to the arrest or conviction of Suarez, described him as a key figure in the rebel group's drug-trafficking operations, including the production and distribution of hundreds of tonnes of cocaine around the world.
"This is an important victory for Colombia," Mike Hammer, the national security spokesman for US President Barack Obama, said.
Started as a peasant army in the 1960s, the Farc grew into a powerful force that once controlled large parts of Colombia and was blamed for hundreds of kidnappings and killings.
But since Alvaro Uribe, the Colombian ex-president, launched an army offensive against the rebels in 2002, the Farc's writ over the country has considerably shrunk.
With Farc-sponsored violence declining, Colombia, once described as a failing state, has also witnessed a five-fold increase in foreign investment.
Al Jazeera and agencies