When the shooting dies down, the silence tells you this is a war zone. Only 20 miles away, San Salvador is a thriving city. San Martin, a market town on the way here, is bustling with traffic and people. But the, on the road to Suchitoto the traffic disappears, as do the people.

"This," says Carlos Avelar, the driver of a Green Cross ambulance, "is what you call guerrilla country." It is an area rife with ambushes and isolated attacks and fighting has been unusually frequent in recent weeks.

A truckload of government troops passes by. Their rifles bristle in every direction. They are young men, some of them very young, and many are obviously terrified. Their eyes are wide and staring at embankments and hillsides where any moment a grenade could be launched, a machine gun open fire.

There is a body lying in a drainage ditch. A small dog is pulling furiously at an arm. The sun is hot and the smell of decay is nauseating. It appears that he was wearing civilian clothes when he died. It appears he has been here for a few days.

A few miles farther along the road the Army has retaken Suchitoto, or at least its buildings. Almost all of its people have fled and only soldiers and their paramilitary friends wander its streets.

Nearby the parched hills around the Guzapa volcano are laced with bunkers and tunnels. This is the height of the dry season, the fields are bare and there is little cover for the insurgents above ground. But the hills still belong to the leftist guerrillas.

The ambulance giving me a ride turns onto a dirt road before reaching Suchitoto, driving slowly, one of its young attendants waving a white flag. All within are aware of the possibility that mines have been laid in the area.

There are small houses, peasant homes amid the burned-out cornfields. But there are no peasants and the houses, little more than one-room shacks to begin with, are now charred shells.

Only the rattle of the beat-up ambulance breaks the silence. Then another sound of war emerges. Children are crying.

The driver stops amid a throng of women and babies in front of what was once a grand old hacienda, a tourist attraction in more peaceful days. Now hammocks are slung from its rough-hewn beams. Everywhere there are children. Many of them are naked. Many have distended bellies from malnutrition, some babies have eyes sealed shut with infections, others are covered with skin lesions from chicken pox. Two suspected cases of smallpox have been discovered.

Of the 1,600 people in the Green Cross camp at La Bermuda, 80 percent are children under 10 years old. The rest are women and a handful of desolete old men. Young men are told not to come here because they might be guerrillas, or might be taken for guerrillas, and the camp could be closed.

The ambulance is bringing food and medicine, but they will soon run out. These people are always on the verge of starving. The all-volunteer Green Cross is the only organization to care for them in this battle zone. But it has no international connections or support and almost no resources.

All it can offer is a neutral haven from the killing -- some of the residents say the guerrillas deliberately avoid action near the camp itself. But a haven is as much as most of the people here could hope for.

"We came here because we were afraid of death," said one young woman simply. Her name is Anna and at 28 she is the mother if five children.

She comes from San Rafael, a small settlement just a few miles away. She said she felt compelled to come here two months ago.

"The authorities came," Anna said. "There was a stray shot somewhere in the area. They burned my house.They burned it with everything.

"My husband is in San Salvador," Anna said. "He is a construction worker. But I don't know what he is doing. I don't know what has happened to him. We have not seen each other. I was alone."

"No," Anna said, she never had anything to do with the guerrillas or their "popular organizations." Many people in her village did, however, so all were suspect in the government's eyes.

"The crime is to be from the village," she said. "Whether you put yourself into politics or not, the crimne is to be from San Rafael. Now it is an abandoned zone."

"They burn for suspicion," Anna said, "or because they find you alone. Because I am alone they think my husband must be with the 'boys"' -- the guerrillas. "They even burned the food. Here in La Bermuda we feel safe. But outside of here, no."

She held one of her youngest children in her arm, resting a hand on the shoulder of another and pulling him closer to her. "We can't even go to our house to pick up what is left. There is no respect for life."

Standing nearby, listening, is a woman of 43 -- she looks older -- who is tending her own small children and grandchildren. Lucia's house was still standing when she left it three months ago. Her husband was killed last summer.

"They took him out of the house at 3 in the morning," said Lucia. She said she did not know who "they" were. She described finding her husband's body, mutilated, the next day.

"There was no reason for it," said Lucia. After the killing "there were days when we ate and many days when we did not. No one helped us at all. Finally we could not stay in the house any longer in such times as these. We came here."

The president of the Green Cross, Francisco Zamora, takes avisitor through the camp, past cooking fires and an open latrine, to the clinic where volunteers in their teens attempt to treat the diseases that are rampant. The more serious cases will have to be taken to the capital. There are no doctors here. No one but the Green Cross will come.

In this fiercely divided country, the Green Cross volunteers insist on neutrality, diassociating themselves even from the Roman Catholic Church, which often is accused of leftist leanings.

In the most dangerous confrontations, these volunteers are often seen moving through the chattering gunfire to rescue soldiers, civilians, guerrillas. They ask no questions of the wounded.

Many of the volunteers are barely more than children, 14 or 15 years old. But that is old enough to be a soldier in this country's contending armies and it is old enough to carry a gun and kill. The volunteers consider it is old enough to try to save lives as well.

The ambulance driver is 30, an engineer who worked at the national unversity until it was closed. "There are times when I go home at night," he said as we again passed by the torn-up corpse on the roadside, "and I sit on the floor of my room and I cry."

News services reported these developments regarding El Salvador:

The Salvadoran government rejected an offer by the Organization of American States to mediate a political settlement between the civilian-military junta and the leftist-dominated opposition, Foreign Ministry sources said in San Salvador.

One of the diplomatic sources there showed reporters an official message to the OAS that said "the revolutonary government of El Salvador does not desire the intervention of the Organization of American States in the search for a solution to the internal problems in El Salvador."

The 28-member organization officially offered to mediate last week at the suggestion of Costa Rican President Rodrigo Carazo.

In Geneva, the United Nations Human Rights Commission called for the appointment of a special representative to investigate "grave violations of human rights and fundamental freedoms reported in El Salvador."