The mayor of the southwestern Colombian town of Toribio, six civilians and three police officers were wounded in a bombing staged by FARC guerrillas, municipal officials said.

Mayor Carlos Alberto Banguero and the other people were wounded by the bomb while walking through the town, which is in Cauca province, on Saturday, Toribio Government Secretary Alberto Ospina told Efe.

"The mayor was wounded by shrapnel in the back and a leg," Ospina said, adding that the official and the three police officers were airlifted by the army to Popayan, the capital of Cauca.

One of the police officers is in serious condition, Ospina said.

The bomb was planted at the entrance to the courthouse in downtown Toribio, which was packed with people because Saturday is market day, Ospina said.

Police blamed the attack on the 6th Front of the Revolutionary Armed Forces of Colombia, or FARC, whose top leader, Alfonso Cano, was killed in Cauca on Nov. 4 by the army.

The FARC, Colombia's oldest and largest leftist guerrilla group, was founded in 1964, has an estimated 8,000 fighters and operates across a large swath of this Andean nation.

The Colombian government has made fighting the FARC a top priority and has obtained billions in U.S. aid for counterinsurgency operations.

A succession of governments have battled Colombia's leftist insurgent groups since the mid-1960s.

In 1999, then-President Andres Pastrana allowed the creation of a Switzerland-sized "neutral" zone in the jungles of southern Colombia for peace talks with the FARC.

After several years of fitful and ultimately fruitless negotiations, Pastrana ordered the armed forces to retake the region in early 2002. But while the arrangement lasted, the FARC enjoyed free rein within the zone.

The FARC is on both the U.S. and EU lists of terrorist groups. Drug trafficking, extortion and kidnapping-for-ransom are the FARC's main means of financing its operations.