Over 40 years, Marulanda, 76, turned a group of 48 armed farmers in southern Colombia into what was to become today's 17,000-strong FARC, which has fought the government and right-wing paramilitaries in a civil war that has claimed more than 200,000 lives.

The aging guerrillero hiding in Colombia's thick jungles has been mistakenly declared dead by authorities at least 17 times.

In February, a Colombian journalist, citing sources close to Marulanda, said he was suffering from prostate cancer and only had six months to live, but FARC's number two leader, Raul Reyes, told AFP in March that his boss was "in good health."

Marulanda, known by his nom de guerre "Tiro Fijo" ("Sure Shot"), was born in Genova, a coffee growing town in the western province of Quindio.

He took up arms as a teenager after several relatives died in political violence that followed the 1948 assassination of Jorge Eliecer Gaitan, a leftist political leader.

Marulanda hid in Quindio's mountains along with 14 cousins and farmers opposing Colombia's conservative government and later embraced the Marxist doctrine after being approached by Colombia's Communist Party.

In 1960, authorities killed his brother-in-law and close friend Pedro Ardila, which prompted Marulanda to declare: "They killed the sheep and they left the tiger."

FARC was born four years later, on May 27, 1964, when Marulanda's group of 48 armed farmers came under attack from the military in Marquetalia, a town in southern Colombia.

Two years later, the group changed its name from the Southern Front to FARC, a group that sought land reform but also power. FARC has used narcotics and "war taxes" on the population to finance its insurgency.

Marulanda remains FARC's political and military mastermind. His official biographer, Arturo Alape, describes him as a reserved and serene man who speaks with a deliberate and paternal tone.

He is married with an unknown number of children, including a daughter who is believed to be part of his rebel group, whose membership includes women and children.

Marulanda held peace talks with former president Andres Pastrana, who led the country from 1998 to 2002. But the negotiations broke off in February 2002 after FARC was blamed for hijacking a commercial airliner and kidnapping two passengers.

The Colombian government says FARC is today holding 1,600 hostages.

Colombian President, Alvaro Uribe has taken a hard line against FARC, which has answered in kind. The group bombed the presidential palace during Uribe's August 2002 inauguration, killing 21 people.

In the run-up to FARC's anniversary, Colombia has experienced some of the worst violence of the past year, and Colombian armed forces and police have been put on alert.

Last week, a series of blasts -- including a car bomb and an explosive device left in a disco -- left 12 people dead in the northwestern province of Antioquia. Authorities blamed the FARC, but no one has claimed responsibility.

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