LOS ANGELES (AP) — Many immigrants flooding across the southern border of the U.S. say they’re fleeing violent gangs in Central America.

Experts, however, say those gangs are actually a byproduct of U.S. policies in the 1990s that sent many immigrants back to Central America after they had been indoctrinated into gang culture in this country.

The violence they took with them easily took hold and flourished in El Salvador, Honduras and Guatemala — countries with weak, dysfunctional governments.

A few things to know:

WHERE DO CENTRAL AMERICAN GANGS COME FROM?

One study estimated some 350,000 Central American immigrants illegally came to Southern California from 1980 to 1985 while trying to escape civil war and corruption in their home country.

They arrived with few English skills and many settled in poor neighborhoods with strong Mexican- and African-American gangs.

To survive and avoid bullying, some formed gangs such as Mara Salvatrucha or joined others such as the 18th Street gang. They committed serious crimes and were sent to prison, where they were further exposed to violent gang culture.

In the 1990s, the U.S. increased deportations of immigrants facing criminal charges, particularly gang members. As many as 1,500 Salvadoran, Guatemalan and Honduran youths were sent back each month to Central America. They arrived with the notoriety of being a Los Angeles gangster.

“There’s this huge explosion in all three of these countries of the gangs and the number of gang members, partially because it’s the way of street kids getting status and reputation, and partially because it’s a way of surviving,” said Tom Ward, a University of Southern California associate professor who has studied the issue.

WHAT IS THE RELATION BETWEEN THE GANGS AND THE INFLUX OF IMMIGRANTS AT THE U.S BORDER?

Many people fleeing Central America say they are running from violence perpetrated by the gangs. But the migration is also an effort to reunify families.

At least 80 percent of youths stopped at the border have one parent or a close relative already in the United States, said Doris Meissner, former commissioner of the U.S. Immigration and Naturalization Service and senior fellow for the Migration Policy Institute, a nonpartisan think tank in Washington.

Family members already in the U.S. have saved enough money to pay a smuggler to bring their children across the border so boys won’t be forcibly recruited into gangs and daughters won’t be subjected to sexual violence.

WHY ARE WE SEEING THIS INFLUX OF IMMIGRANTS, ESPECIALLY CHILDREN, NOW?

Word of mouth in Central American is strong and there is a pervasive belief that the U.S. has been relaxing its immigration stance toward minors. The belief was spurred by recent discussions about possibly changing U.S. immigration policy and by a change in U.S. law in 2008 that provided more rights to minors at the border that included a hearing before a judge.

At the same time, a crackdown on cartels caused those criminal organizations and their trafficking operations to spread from Mexico to Central America. More people decided it was time to leave for the U.S. where they believed they would be allowed to stay.

Migrants were told to have their children turn themselves into the Border Patrol and they would be given a permit to enter the U.S., said Eric Olson, associate director of the Latin American Program for the Woodrow Wilson International Center for Scholars.

The permit, however, was really an order to appear for a deportation hearing.

Even so, with court backlogs and a shortage of judges, it can take as long as three years to get a hearing. In the meantime, children are reunited with family in the U.S. and live far away from the violence at home.

WHAT HAVE THE CENTRAL AMERICAN AND U.S. GOVERNMENTS DONE AND WHAT ARE THEY DOING NOW?

Since 2008, the U.S. has approved $803 million for the Central American Regional Security Initiative, which includes efforts to disrupt narcotics trafficking, support development of strong police and justice institutions, and prevent crime and violence. The efforts have generally focused on preventing youths from joining gangs — not trying to get gang members out of the life. And the impacts of these programs have not been effectively measured.

The Obama administration is now requesting that Congress approve $3.7 billion in emergency funding to deal with the border crisis. The proposal includes $300 million to address repatriation and reintegration efforts among other issues. Funding would also pay for a media campaign to get the word out about the dangers of the journey to the U.S. and the lack of potential immigration status when people arrive. It would also go to gang intervention and prison reform.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.