Hundreds of soldiers attacked a right-wing paramilitary force in central Colombia, killing and capturing dozens of fighters, the army reported Saturday.

The ongoing combat in Antioquia province comes days after President Alvaro Uribe took power on promises to pacify illegal armed groups fighting in the nation's 38-year-old civil war.

Army spokesman Capt. Jose Espejo said soldiers killed 20 members of the paramilitary's Metro Block and captured 17 others during fighting that began late Friday outside Segovia, 186 miles north of the capital, Bogota.

The paramilitary block -- part of a nationwide force -- is waging an illegal war against leftist insurgents in Medellin, Colombia's second-largest city, and throughout Antioquia province. Three soldiers were wounded in the fighting.

The offensive may help ease concerns that the U.S.-backed military under the new president would give free reign to the paramilitaries.

Human rights monitors have frequently criticized the military for collaborating with paramilitary forces, which last year were responsible for most of the massacres committed in Colombia.

Uribe -- a former Antioquia governor -- also has been dogged by charges that he's tied to the paramilitaries.

The government also is fighting the leftist Revolutionary Armed Forces of Colombia, or FARC, which launched a mortar attack on the Colombian capital last week just as Uribe was being sworn in, killing 19 people. About 3,500 people die every year in Colombia's civil war.

Uribe was swept into office on promises to crush the rebels on the battlefield and force them into peace talks.

Meanwhile, the new government named army commander Gen. Jorge Enrique Mora to replace outgoing military commander Gen. Fernando Tapias.

During the announcement late Friday, Defense Minister Martha Ramirez described Mora as an "official of high performance and grand leadership." Gen. Carlos Alberto Ospina takes Mora's old job.

As the new armed forces chief, Mora will lead the fight against a booming cocaine trade and entrenched insurgents dedicated to toppling the government.

Traveling through a southern drug growing region Saturday, Uribe said the government would pay farmers in Putumayo province $2,000 annually for destroying their drug crops and planting trees.

A previous U.S.-funded crop substitution program in Putumayo -- Colombia's cocaine heartland -- recently hit the rocks earlier this year. A study blamed the failure on the region's thin soil, which has thwarted farmers' efforts to grow legal crops.

Washington has given Colombia dlrs 1.7 billion over the past few years to fight drugs and poverty.