Colombia's main leftist rebel group, the Farc, has confirmed the death of top commander Manuel Marulanda, saying he died of a heart attack.

The long-time commander and founder of the group died in his companions' arms on 26 March, according to a Farc statement broadcast by Colombian media.

His death was reported on Saturday by the military and media.

Thought to be 78, the rebel leader had been rumoured to suffer ill-health, including suspected prostate cancer.

The Farc announced that Marulanda, whose real name was Pedro Antonio Marin, would be replaced as overall commander by Alfonso Cano (real name: Guillermo Leon Saenz), already regarded by some as the group's ideological leader.

Reporting from Colombia, the BBC's Jeremy McDermott notes that the Farc is suffering its worst period yet as it celebrates its 44th anniversary.

Morale is at an all-time low and the loss of an inspirational figure like Marulanda could provoke more desertions and lead to a break-up of the group, our correspondent says.

However, Alfonso Cano could bring much-needed change to the Farc and seek to end the series of defeats that the rebels have suffered for the last five years, he adds.

Air strikes

Confirmation of the leader's death was made in a televised address by senior Farc official Rodrigo Londono Echeverri, alias "Timochenko".

"The great leader is gone," he said in the message, broadcast on Colombian TV.

Marulanda, nicknamed "Tirofijo", or "Sureshot" in English, had led the Revolutionary Armed Forces of Colombia since its foundation in 1964.

Speaking on Saturday, the head of Colombia's Joint Chiefs of Staff, Admiral David Rene Moreno, said government planes had bombed the area where Marulanda was believed to have been staying three times.

However, there had been no air strike on the actual date of his death, the admiral said.

He described Marulanda's death as "the hardest blow that this terrorist group has taken since 'Sureshot' was the one who kept the criminal organisation united".

Formidable force

Pablo Casas, an analyst at Bogota think-tank Security and Democracy, compared the Farc to a "dying giant, dying slowly".

"I don't see any factor they can use to keep a strong structure," he told Reuters news agency.

The Farc still have anything up to 10,000 fighters and are flush with drug money, so few believe the rebels are finished, our correspondent says.

But the US-backed offensives by President Alvaro Uribe have pushed the Farc on to the defensive.

Before news of Marulanda's death, two other commanders were killed and an iconic female leader surrendered.

It remains to be seen if a change a leadership will lead the guerrillas more towards a negotiated settlement or harden their resolve to keep fighting to the bitter end, our correspondent adds.         

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