It began four years ago, when some Salvadoran teenagers began hanging out with one another near their homes in Adams-Morgan. They socialized after school, played soccer together, dressed up in their best clothes for weekend visits to nightclubs.

Across the Potomac, in the Arlandria section of Alexandria, another group of Salvadoran immigrants was beginning to form. They too enjoyed sports and dancing and socializing with others who shared their language and culture.

Eventually the members of the two groups began to run into one another, often on the crowded floors of area dance clubs. But instead of finding common ground, they found trouble and violence.

In just over a year, two teenagers -- one from Alexandria, one from the District -- have been killed in a running feud between the groups that police and several teenagers say began in 1989. At least two others have been wounded, and several more have been shot at, they say.

Most of the violence has stemmed from arguments that began in local nightclubs. Police say that some of the arguments were over young women, but several youths from both sides said women were not the issue and that very little provocation was needed to start a fight.

About 50 youths and a few men in their early twenties belong to the District group, known variously as La Mara de R Street or La Mara de Washington (la mara means "gang" or "group"), according to several members, former members and police. Many of the District youths come from the Salvadoran town of Intipuca.

At its peak, the Alexandria group -- known as the Chirilaguas, after a town near Intipuca called Chirilagua, where many of its members were born -- numbered about 30, according to community activists and an Alexandria police detective.

The feud has taken a toll on the Chirilaguas; one member said the group all but disbanded recently in the wake of the violence and police pressure.

Neither group has been classified by police as a street gang, and the reported dissolution of the Chirilaguas may mean an end to the feud.

Still, school officials and community activists are worried. They say they fear that the Salvadorans' feud and the violence it spawned are early signs that the Washington area is no longer immune to the street gang warfare that has plagued many other large American cities.

"Right now it's more of a social thing," the Rev. Donald Lippert, of Sacred Heart Catholic Church in Adams-Morgan, said of the groups' activities. "But I think it can get worse."

Those who know the groups say they formed out of the young immigrants' natural desire for companionship in their new country, one whose ways often seem strange and confusing.

"They band together for the same reasons any other kids would band together -- they feel comfortable together," said Jamie Fishman, of Arlandria, who teaches English as a second language at Lincoln Junior High School in the Columbia Heights section of Northwest Washington.

"There's a lot of confusion" among such immigrant teenagers, said Quique Aviles, coordinator of the leadership program at the Latin American Youth Center in Adams-Morgan. "They come from a completely different land, a different culture, a different language, a different way of doing things."

One teenager, described by school officials and immigrant youths as a leader of the D.C. group, sought to distinguish it from the larger and more violent groups in such cities as Los Angeles, which often run criminal enterprises.

"We're not a gang," said the youth, who did not want to be identified. "We take care of each other, that's all. We take care of each other."

The group, he said, is not particularly turf conscious, as most genuine street gangs are. Several teenage Washington Salvadorans say people join to gain status on the street and in nightclubs.

"It's about who's the toughest, who dresses the nicest, who's the most stylish," said another youth who used to run with the Washington group. "You have to be able to fight. If you see one of yours is in a fight, you have to jump in and defend him."

Participants in the feud gave different accounts of what started it, but agree that it began as an argument in a nightclub. Words quickly gave way to fists, and fists escalated to bats, then knives and guns.

The first death happened in January 1990, when Kelvin Alvarez, 17, was shot to death on his Alexandria doorstep, a week after he had squared off against members of the D.C. group in a fight outside a Washington nightclub.

Washington resident Henry Diaz, 18 at the time, has pleaded guilty to first-degree murder in the killing. Jaime Ernesto Mira-Lopez, 21, also of Washington, pleaded guilty to being an accessory after the fact.

The violence flared again 11 months later. On Dec. 8, Mauro Canas, 18, of Alexandria, was stabbed in the legs and back at an Alexandria restaurant. He recovered.

Three weeks later, 15-year-old Edwin Merino, of the District, was shot to death outside the Tracks nightclub in Southeast Washington, allegedly in retaliation for the Canas stabbing. Several Washington youths and a D.C. detective said another person in the car, not Merino, was the intended victim.

Jose Augustin Guevara, 18, and Fermin Rivera, 19, both of Alexandria, have been charged with first-degree murder while armed in connection with Merino's killing.

Ana Merino, the slain youth's mother, said last week that she didn't learn of the feud until after the killing. At her son's funeral, she said, she asked a leader of Edwin's group why he couldn't put a stop to the violence. She said she got no response.

"It's absurd," Merino said in Spanish. "What are they fighting about? What are they fighting about? They're sick in the head, wanting to kill and hurt each other. Nobody has a right to take someone's life, except God.

"Someone should bring the two sides together and ask them, 'What do you want?' " she continued. "I hope to God this will end. It can't go on like this."

The youth identified as a leader of the D.C. group said it doesn't take much to set off a fight.

"In Tracks it gets full. You can brush into people. If you bump into someone and they don't like it . . . . " He shrugged. "We go to clubs to have fun, but if they want trouble, we're not going to run."

That willingness to fight has driven some Salvadoran youths away from the groups. One 16-year-old said he recently dropped out of the R Street group because he was tired of the cycle of violence the group had entered. Those who remain, he said, will "either end up dead or in jail."

Community activists are saddened by the fighting, noting the groups' common heritage and struggles.

"The tragedy is that both suffer from the same problems -- a lack of cultural activities and outlets and a lack of jobs," said Jon Liss, staff coordinator of a tenants' support committee in Arlandria.

That common bond carries little weight with Mauro Canas, the victim in December's stabbing, who said he can't envision becoming friends with anybody from the D.C. group. "I don't trust them," he said.

A District detective familiar with the feud said that since the Merino shooting, police have made a point of telling members of both groups that they had better "chill out."

But the detective said he isn't confident that the animosity has been laid to rest. "They just don't let it go," he said.