Editor's Note: This is the second in a four-part series on the troubles in the Congo, compiled from Fox News' Steve Harrigan's first-hand reports in the war-ravaged African region.

BUNIA, Democratic Republic of Congo -- After six years of war, some adults have become as helpless as small children, and some children have been forced to become adults.

Most are orphans, some not much bigger than their rifles, but their actions are hard to predict, especially since fighting often takes place under the influence of drugs. Aid groups estimate that about half of the people fighting in Bunia (search) are children.

• Video: Children Fight Congo's Wars

Two ethnic groups battle for control of the town: the Lendus (search), which make up the majority of the population, and the minority Hema (search). The Lendus fled into the hills following the Hema capture of the town in late May.

Caught in the middle are tens of thousands of Congolese, who have fled their homes once already to seek shelter at a United Nations (search) compound. Now, even that refuge is no longer safe.

Fighting is almost nonstop.

Gunfire starts suddenly, unexpectedly, like a summer storm. Once again, men, women and children run for their lives, carrying what they can on their heads.

As the gunfire increases, people get as low as they can. A child hides underneath a blanket, her only shelter.

The stress is too much for one woman, who collapses. And as her mother looks on, no help is in sight.

There is panic that fighters have infiltrated the camp.

One man is being roughed up in view of Fox News cameras while gunfire goes off all around the compound. The man was apparently found with a grenade and was taken into custody.

If the camp is overrun, there could be a slaughter.

Throughout the gunbattle, U.N. troops serving as peacekeepers do not fire a shot. Their mandate is to fight only if the compound comes under direct attack.

The fighting lasts five hours, then ends as suddenly as it began. Red Cross (search) workers march out to bury those killed but it's not safe for them to go much beyond the center of town. That means for some victims of an African world war there is no relief, even after death.

But some images resist explanation. They are hard to look at, and harder to understand in a world turned upside down by five years of war. Few are paying any attention.

Part 3 will focus on the victims of Congo's wars.