The principals and police officers meeting at a Greenbelt high school in hopes of heading off a spike in local gang violence as the school year begins weren't the only authorities talking yesterday about the problem of Mara Salvatrucha, or MS-13.

At FBI headquarters, the head of the MS-13 national task force was gathering with 80 law enforcement officials from around the country and from several Latin American nations for a one-day summit.

Although the gathering in Maryland captured the local impact, the summit signaled the international scope of the problem, which has shot back into headlines in the area in the past couple of weeks.

The meeting, scheduled before the recent spate of stabbings and slashings in Maryland, was held behind closed doors with officials from El Salvador, Guatemala, Honduras and Mexico.

Collectively, they painted a chilling picture of the problem they face and the problem the United States will face if it does not slow the rise of the MS-13 and its rivals, Supervisory Special Agent Robert F. Clifford, the head of the national task force, said afterward.

"We need to attack this nascent, this growing infrastructure of MS-13," Clifford said, "before it has a chance to grow into the organized criminal enterprise we see in Central America."

The gang's members on the West Coast are increasingly engaged in organized crime such as extortion, Clifford said, and there are signs that such activities are likely to spread east.

With the gang spanning many borders, ensuring that information spans those same borders has been a key objective, and Clifford said the meeting yesterday advanced those efforts.

But he also acknowledged that the law enforcement community is not as far along as it needs to be. "Gang information on a national basis is hard enough," he said. Collecting information just among local and federal agencies and organizing it into a coherent body of data is a work in progress, he said, and sharing that information with other countries is an even taller order.

For the representatives of the Latin American countries, the meeting was an opportunity to convey face to face the depths of the problem in their countries and the need for coordinated action in the Americas.

Julio C. Godoy-Anleu, Guatemala's vice minister of government for security, said he fears that people in the United States do not know how dangerous and destabilizing these gangs have become in Central America and do not appreciate the risk they pose to Washington and other areas where the gangs have taken root.

"I think the problem is bigger than the people of the U.S. think," he said. "If you stay in the country, in Guatemala, you will understand the real dimension."

The mistake, he said, is to see it only as a security problem. "This is a social problem," he said.

Many leaders and experts have said that the political turmoil and violence of a couple of decades ago, coupled with the corruption and poverty in their communities today, have left many young people angry and hopeless -- and vulnerable to the lure of gang life.

Godoy-Anleu and other police officials said one of their most serious concerns is the prisons in their countries. Crowded with violent gang members, the prisons are often strained further by the periodic influxes of criminals coming home, voluntarily or involuntarily, from the United States.

This week, at least 35 people were killed in riots at seven Guatemalan prisons in what authorities believe was one gang's coordinated strike at a rival gang, according to the Associated Press.

A day-long summit at FBI headquarters in Washington gave U.S. law enforcement officials and authorities from El Salvador, Guatemala, Honduras and Mexico an opportunity discuss the problems they face in dealing with such gangs as Mara Salvatrucha. Robert F. Clifford of the FBI heads the national gang task force.