IN THE JUNGLES OF SOUTHERN COLOMBIA - Army Maj. Arnulfo Sanchez had been trudging with his troops through the jungle for more than a month when he glimpsed the outline of wooden huts concealed amid the undergrowth.
Minutes later he heard shouts and a brief volley of gunfire, as leftist rebels occupying the huts fled.
His battalion nervously moved in - and discovered one of the biggest rebel munitions factories the Colombian military has ever come across.
The seizure of the encampment - shown to a handful of journalists on Tuesday, four days after troops discovered it - in the jungles of southern Colombia's Guaviare state was the latest blow the army has dealt the Revolutionary Armed Forces of Colombia, known as the FARC.
But the clandestine munitions factory and the massive stockpiles of explosives, grenades, mortars and ammunition underscores the magnitude of the task the army faces as it wages an offensive against jungle strongholds of the FARC, which has been battling to topple a succession of elected governments for 40 years.
Inside the seized compound were four generators each capable of providing power to a small village, dozens of Suzuki boat engines, chain saws, electric drills, construction equipment, toilets, television sets and refrigerators. There were aluminum and steel tubes and work shops to fashion them into mines, mortars and rockets of varying shapes and sizes.
There also were rockets of the type FARC rebels used to attack a marine outpost in southwest Colombia on Tuesday, killing at least 14 soldiers and wounding 25. It was not immediately clear if the weapons used in the deadliest rebel attack in two years were made here.
"The terrorists invested a lot here," said army Gen. Carlos Alberto Fracica. "If we can defeat them here, they will have nowhere to run. But we are at a disadvantage. They know the jungles better than we do."
The rebels have constructed a network of dirt roads - often hidden from the air by the jungle - which, along with rivers, link an elaborate array of fortified rebel camps and stockpiles of equipment and arms.
At the compound, an acoustic guitar hung from a nail next to a pantry, which contained a shiny tea set, ceramic plates, spaghetti and imported chocolate biscuits.
"When we entered the camp we couldn't quite believe it," recalled Sanchez. "But little by little we are taking away their logistical base, limiting their ability to wage war."
Fracica, in an interview with The Associated Press as he flew to the arms factory aboard a helicopter, said no troops were killed as they seized the compound. Troops on the ground cleared a small landing zone and guided in the general's chopper by lighting fires, which sent smoke streaming above the jungle canopy.
Fracica is the commander of the offensive in southern Colombia, dubbed "Plan Patriot," aimed at depriving the rebels of their main logistical base and killing or capturing FARC leaders.
Some 15,000 troops are scouring 46,000 square miles of jungle on foot for signs of FARC installations, usually located near rivers, lakes or ponds, since the rebels require access to water, Fracica said.
Government troops spend up to three months straight in the combat zone, supplied by aircraft that take off from any of seven army bases dotted around Guaviare, Caqueta and Meta states.
Military commanders say intelligence indicates the FARC leaders rarely stay in one place for a more than a couple days, leading to a cat and mouse game with the military.
The few civilians living in the area - most of whom tend coca crops, the raw ingredient in cocaine - provide little help - they usually have sons and daughters in the FARC's ranks.
Before leaving the seized arms factory, Fracica sought to fire up the troops, who soon must move deeper into the jungle in search of more rebel hideouts.
"God and victory!" he hollered.
"God and victory!" they shouted back.