SAN JOSE DEL GUAVIARE, Colombia -- (AP) -- Waves of helicopters carrying troops lifted off from a staging area in Colombia's coca-growing plains Thursday, as the U.S.-backed military hunted down a wounded column of more than 1,000 leftist rebels.

 After many years on the defensive, the military is trying to show it can hit back at the rebels. The offensive comes a week before the arrival of a high-level U.S. delegation, and with the spotlight on Colombian President Andrés Pastrana over the rebels' misuse of a Switzerland-sized safe haven he ceded them in peace talks.

 The army's week-old offensive is unlikely to prove decisive in a 37-year war that shows no signs of letup. But it demonstrates how the military -- stocked with U.S.-made combat helicopters and growing aid and training from Washington -- has been faring better lately on the battlefield against the Revolutionary Armed Forces of Colombia, or FARC, the country's largest insurgency.

 HIDING IN JUNGLE

 The rebels on the run near San José del Guaviare are believed to be hiding in the jungles to the east, cut off from their base and running low on food and other supplies.

 A half-dozen deserters say the guerrillas are desperately trying to make their way back to the rebel's southern safe haven after their plan to attack towns and an army
 base in Colombia's southeast was foiled by a government counterattack -- one of the biggest in recent memory.

 Leaflets dropped from helicopters invite the insurgents to surrender.

 ``They are running out of food. Their radios must be losing power. They have many wounded,'' said an army colonel commanding a brigade, who refused to give his name for security reasons. ``Our mission now is to eliminate them.''

 The military's success here and in other recent battles would have seemed impossible just a few years ago, when the 16,000-strong FARC was routinely battering an
 undertrained army.

 In June, helicopter-borne troops turned back another attempted large rebel strike, killing 26 guerrillas in a battle in which 30 troops also died. In November, a nearly
 400-rebel unit was dismantled by the military after being spotted from air traversing a high-Andean plateau.

 Washington approved a $1.3 billion aid package last year devoted to helping Colombia fight drugs. However, there are voices calling for U.S. military aid to be targeted directly against the rebels -- something critics worry will draw the United States into Colombia's brutal war.

 A U.S. delegation is scheduled to arrive in Bogota next week, the first such visit since President Bush took office. The delegation is expected to raise concerns with
 Pastrana about the enormous jungle sanctuary he ceded them to initiate peace talks, a U.S. official in Washington said Thursday.

 RETRIEVING BODIES

 In the battle zone Wednesday, a Blackhawk helicopter skimmed over jungle canopy to retrieve bodies of some of the dozens of rebels killed in combat. The door gunners, looking insect-like with dark visors pulled over their faces, hunched over M-60 machine guns as the jungle sped past in a blur.

 The U.S.-trained pilot, army Maj. Camilo Rosso, spotted smoke marking where the bodies of two rebels lay, and put the helicopter into a hover about 100 feet over the spot.

 A commando leapt out of the door of the helicopter, rappelled to the ground, stuffed the shot-up corpses of two rebels into black body bags and then tied them to his rope. When the helicopter soared into the sky, the soldier dangled below, straddling atop his grisly cargo.

                                    © 2001