July 8 (Bloomberg) -- Colombia’s biggest guerrilla group is shifting its strategy to urban terrorism after suffering battlefield losses that threaten its survival, national police Chief Oscar Naranjo said.

The leader of the Revolutionary Armed Forces of Colombia, Alfonso Cano, has unleashed a wave of bombings in the nation’s cities following the rebels’ worst defeats in 45 years of rural and jungle fighting, Naranjo said in an interview. With their territory shrinking, the guerrillas aim to stoke fear in more densely populated and economically important areas, he said.

“Terrorism is the weapon of the weak,” said Bogota-based risk analyst Andres Villamizar. “It’s easier to attack civilian targets than fight military battles so we can expect to see a lot more of this going forward.”

The FARC, as the drug-funded group is known, is maneuvering to remain “relevant” ahead of presidential elections next year and show that President Alvaro Uribe hasn’t defeated them, Villamizar said. Intelligence officials say FARC members also plan to return to attacks on infrastructure such as electricity pylons, a strategy that stifled economic growth until Uribe’s offensive, which helped set off the fastest expansion in three decades in 2007.

‘Weapon of the Weak’

“They are looking for how they can make the most impact possible,” said Naranjo, 52, who has headed the national police for the past two years. “They still have the capacity to inflict harm.”

Last year, the FARC was weakened by the death of three top leaders, desertion by dozens of its most seasoned commanders, betrayal of one of its security chiefs and the rescue of its highest-value hostages, former presidential candidate Ingrid Betancourt and three U.S. contractors. Colombian armed forces pushed most of the guerrillas into remote jungles and kept them on the run, according to released hostages.

“Last year was a terrible year for the FARC,” said Naranjo, dressed in an olive uniform with decorations sewn to the chest.

The result for Cano, who last year replaced Manuel Marulanda after he died from a heart attack at 77, was the need to change tactics, Naranjo said.

In the last weekend of June, the FARC set off two explosive devices in Bogota and tossed a grenade at a gas station. The police have intelligence indicating that rebels are funneling money to Bogota-based militants for attacks on electricity towers and businesses, Caracol radio reported July 3, citing Bogota police commander Colonel Cesar Augusto Pinzon.

Car Bomb

The group killed two in a car bombing of a police station in Cali in February shortly after setting off an explosion in front of the city’s courthouse. In January, the FARC detonated a bomb at a Blockbuster Inc. video store in an affluent part of the capital, killing two.

Uribe on July 4 urged Colombians to be vigilant for the new threat of “high profile” attacks planned ahead of the 2010 elections.

The group’s impact in Bogota has been limited since 2003, when it killed 37 people and injured 200 with a car bomb at the posh social club El Nogal. Last year authorities found at least 30 kilograms (66 pounds) of depleted uranium in the city.

Cano, 60, a former anthropology professor from Bogota whose middle-class background sets him apart from the FARC’s peasant base, and Mono Jojoy, his most senior commander, are still in Colombia, while many of the other leaders live in hiding outside the country, Naranjo said. The FARC operate in at least 17 countries worldwide, he said.

‘The Hunt’

“We know about where Cano and Mono Jojoy are,” the police veteran of 33 years said, declining to elaborate. “The armed forces will keep up the hunt. What’s so important is that Colombia has to be sure that its neighbors aren’t becoming places for the FARC to hide.”

Computer files found last year after a cross-border bombing raid into Ecuador that killed the rebels’ second in command, Raul Reyes, showed Ecuador’s President Rafael Correa and Venezuela’s Hugo Chavez provided financing, supplies and border area sanctuary to the FARC, the government has said. Both leaders have denied any connection.

The group has lost almost half its fighting force since Uribe took office in 2002 on a pledge to attack the drug-funded group in their jungle camps. Hunger and disillusionment have encouraged as many as 11,200 members to risk execution and desert the ranks, cutting their numbers down to about 8,000, the defense ministry said.

Thanks to the offensive, kidnappings fell by 84 percent to 437 last year and terrorist attacks by 79 percent to 347 in 2008, the Defense Ministry says.

To contact the reporter on this story: Helen Murphy in Bogota at hmurphy1@bloomberg.net

Last Updated: July 8, 2009 01:02 EDT