A wave of violence has claimed the lives of three mayors and nine other Christian Democratic Party activists in this bitterly divided country during the past three weeks. The latest victim was Evangelina Garcia, a widow who recently had been named interim mayor of this village.

Garcia, 47, and her 18-year-old daughter were gunned down in their dirt-floored kitchen Friday night, like her predecessor a victim of the political turmoil that has cost tens of thousands of lives in the past 30 months. The killings in this village, especially, suggest how indecisive election results combine with enmities and vendettas dating back years to inflame such violence.

Unlike many previous political killings here, the recent wave of slayings has led to some arrests. Three members of the paramilitary civil defense unit here have been picked up in connection with the killings, and more are being sought. Meanwhile, three other Civil Guardsmen were detained in El Paisnal for allegedly killing its Christian Democratic mayor May 22.

The government armed forces publicly have denounced the killings that began May 12, with the slaying of an alternate delegate to the legislative assembly in San Salvador.

No one, not even the embittered Christian Democratic leadership, is accusing the newly ascendant right-wing leaders of ordering or condoning such acts.

Nevertheless, the large-scale violence in this country often has been at least as much a result of the general environment created by those in power as of direct orders, and since the March 28 constituent assembly elections, that environment has become increasingly poisoned by hatred at the local levels that the voting did nothing to appease.

When former president Jose Napoleon Duarte heard last Wednesday that six party workers had been abducted and killed in the little town of La Primavera north of the capital he turned to a visitor and said flatly, "This is the beginning of revanchismo"--the process of revenge.

The wave of killings comes amid signs that the human rights situation here generally is worsening after a hiatus surrounding the elections. The dark lava beds at El Playon north of the capital once again are a dumping ground for victims of the violence here, and the romantic tourist vista at the Devil's Door now overlooks bodies thrown from the precipice.

While acknowledging contributions by the armed forces to the democratic process here, the Christian Democrats said in a paid newspaper advertisement Saturday that "the recent elections have generated a process of confusion and politicization on the part of elements in the Civil Guard, troops and agents in the security forces, and even some military commanders who for various reasons have taken up the banners of distinct political parties in various locations and are trying to arrange every affair by means of arms."

The Army has responded with its own advertisement deploring the killings and calling for the murderers to be brought to justice.

The political allegiances of this town high in the mists of coffee-growing mountains about 20 miles east of the capital traditionally were with the official National Conciliation Party and, more recently, with its partisans in the new and powerful right-wing Nationalist Republican Alliance of Roberto D'Aubuisson, a cashiered Army major.

The first of these parties was instrumental in building up paramilitary Civil Guards, especially through the now nominally disbanded group called ORDEN. The second, formed less than a year ago, courted the paramilitary units as "anonymous heroes," in D'Aubuisson's phrase, and made them a key part of its constituency and its rabidly anticommunist campaign.

The local branch of the Christian Democratic Party was founded in the mid-1960s by a prominent local man named Catarino Martinez.

It grew slowly and lost a number of elections. Finally, in 1974, the Christian Democrats were sure they had taken the office of mayor at the ballot box, but the vote counters were from the official National Conciliation Party, and they declared their own man triumphant.

On April 30, 1974, the day before the mayor-elect was to take office, the Christian Democrats occupied the town hall. The Army was called in, and the occupiers were removed, jailed, in some cases tortured, according to one local activist who now lives in San Salvador.

Then, some villagers said, a campaign of intimidation was begun. The local paramilitaries used lists of alleged guerrillas, said Rafael Martinez, or spread word that people were on lists that were never seen.

The situation changed after the coup of October 1979 and the entrance of the Christian Democrats into the government in January 1980. Under provisions of the then-ruling junta allowing them to appoint mayors, the Christian Democrats immediately started to shore up their political bases by naming their people in most of the country's 261 municipalities, including this village.

The local paramilitaries struck back quickly. On Jan. 21, 1980, they killed Catarino Martinez, his wife, one of his grandchildren, a son-in-law and a visiting friend.

The local paramilitary commander, Arturo Iglesias, was jailed for the murders, but the pattern remained unchanged. The Martinez survivors never have returned.

One of them, Rafael Martinez, said, "From then on, it was like a hunt. The zone was practically militarized" around the little Candelaria settlement, where the Christian Democrats had made some strides.

Last August, Evangelina Garcia's little house was dynamited, according to an affidavit she filed at party headquarters. Several months before that her brother, Miguel Angel Garcia, had been killed and her first home burned to the ground.

The first mayor named by the party in San Salvador, Teodoro Eliazar Cruz, refused to sleep here, Christian Democratic officials said. Instead, he came each day on a bus.

By the time elections were held in March for a constituent assembly, this town voted overwhelmingly for D'Aubuisson--903 for him and 294 for the Christian Democrats.

Even though D'Aubuisson had won, the local administration remained unchanged in the two months after the elections while the politicians tried to figure out how to organize the national government.

One Christian Democratic leader in the capital, San Salvador Mayor Alejandro Duarte, said that once a final decision is made on the mechanism for apportioning mayoralties among the three dominant parties San Francisco Chinameca probably will wind up with a D'Aubuisson supporter as mayor.

Someone, however, was apparently unwilling to wait for the change.

On May 13 armed men wearing hoods dragged Christian Democratic Mayor Cruz off the San Salvador bus and killed him before the eyes of the horrified passengers.

Evangelina Garcia was named the party's new mayor and was supposed to take office today.

Instead, at about 6 p.m. Friday, she was forced back from the door of the smoke-filled cooking hut by armed men shouting obscenities. They shot her four times in the head and shoulders. Her 18-year-old daughter Elsa was killed with a bullet in the face.

A brother, Eliseo Garcia, 44, remains shaken, saying his family never before had ventured into politics.

"We don't have anything here," he said. "All we have is fear."