Salvadorans Flock to Shelters as Fighting Ebbs : Central America: The army gains the upper hand as rebels withdraw from some areas of the capital.

As fighting slackened in some guerrilla strongholds, thousands more Salvadorans fled bombed-out neighborhoods in the capital Saturday, filling churches, schools and stadiums in one of the largest exoduses in this country’s tortured history.

A Salvadoran Red Cross spokesman, Pedro Varela, said 19,000 people have crowded 42 shelters over the last week of heavy combat in the capital, which has claimed at least 900 lives and left another 2,000 wounded.

The number of refugees is fast approaching the 22,000 who took emergency shelter after an earthquake in 1986, Varela said, and could easily double with a lull in the war.

“The bombs fell so close to our house--that is what gave us the valor to walk though the bullets and get out of there,” said Miriam Diaz, 28, who set up camp in the capital’s main soccer stadium with her parrot and eight other members of her family. “It was a tremendous nightmare.”

Air force planes and helicopters strafed parts of the poor neighborhoods of Soyapango and Mejicanos early Saturday, trying to squeeze the leftist guerrillas into smaller and smaller areas of the capital.

The guerrillas said in a clandestine broadcast that they shot down an air force A-37 fighter-bomber with machine-gun fire Saturday over the eastern city of San Miguel. An ABC News camera crew filmed the aircraft as it was apparently hit, and an air traffic controller in San Miguel confirmed that it crashed. He said the pilot bailed out.

In San Salvador, most of the rebels holding Mejicanos had withdrawn by dawn, fleeing through sewer pipes and tunnels after mining some entrances to that northern neighborhood of 100,000 people, residents said.

The rebels allowed hundreds of trapped and wounded civilians to flee along unmined paths before the army went in to look for the few rebels who remained.

“They took (civilian) clothes from the people and put them on. Then, they buried their weapons and left,” said Jose Mejivar, 55, as he abandoned Mejicanos with everything he could fit in a sack.

But in Soyapango, the rebels held their ground, fighting off ground troops in house-to-house combat and withstanding another round of aerial strafing and rocketing in the afternoon.

“There is tremendously strong resistence in Soyapango,” said a Western diplomat. “They are well armed and surprisingly tenacious . . . “

The combat in Soyapango, in south San Salvador, appeared to be centered in two six-square-block areas that sprawl over steep hills.

The U.S.-backed Salvadoran army has gained the upper hand since the rebels launched the offensive. But it is not clear whether the rebel retreat from Mejicanos, or from Zacamil a day earlier, is permanent or simply a regrouping for new attacks.

The army has been spread too thin to even try to drive the guerrillas from two northern suburbs, Apopa and Ayutuxtepeque, which the government has held virtually uncontested for a week.

Fighting has affected virtually every part of San Salvador and its 1.5 million people since the Farabundo Marti National Liberation Front rebels descended on the capital Nov. 11.

During a tour of neighborhoods still being fought over, residents and relief workers pleaded with American reporters to “tell them to stop the bombing”--a reference to the government air strikes.

“This is not the jungle. They have no right to bomb here,” said Leopoldo Campos, 47, who left Mejicanos weeping and pressing a bloodied gauze pad to his forehead. “Tell them to take the airplanes away from here.”

Campos was wounded and his 17-year-old son was killed, he said, when “a bomb fell on my house” Friday.

For days, Salvadorans have complained, on the one hand, that the guerrillas will not let them leave their embattled neighborhoods, lest the army lose all restraint in attacking them.

On the other hand, they say, the army has put their neighborhoods under curfew and then bombed them, sometimes without warning. Many have chosen to sleep outdoors on the theory that all houses are suspected rebel hide-outs.

“First, the terrorists won’t let us leave; then, the government refuses to evacuate us,” said Nicolasa Quintanilla, 50, who fled to the soccer stadium Friday.

“We’re being squeezed by both armies.”

Relief workers estimate that hundreds of people wounded in combat zones cannot be evacuated.

Red Cross ambulances raced to and from an entrance to Mejicanos on Saturday, taking away more than a dozen wounded civilians.

In its third such appeal in four days, the International Red Cross urged the government and the rebels Saturday to declare a six-hour truce so that it can evacuate the wounded. So far, the rebels have agreed to the truce, but the government has rejected it.

As a reporter toured the soccer stadium, a 7-year-old boy asked him: “When are they going to bring us medicine?”

Many of the 300 people sprawled on blankets and flattened cardboard boxes there had minor wounds. They also complained that nobody was providing food for them and that, because they are unable to work, they lack money to buy their own.

The plight of those trapped in combat zones was worse. Many have no electricity or food.

In Apopa on Saturday, three female guerrillas explained to reporters that the 1,100 people in a rebel-held neighborhood were prepared to hold out with them.

“On every block, in every alley, people are building air raid trenches,” said Sara, who brandished an assault rifle. “We are the army of the people.”

But as they left, reporters were mobbed by residents who said they felt trapped and wanted help.

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