"Child" Refugees coming over the border.

Below is what I think is the most accurate description of the problem. There is hardly a mention of this invasion in the mainstream media. Why would that be?

A surge in unaccompanied minors from Central America crossing the border illegally into Texas has so overwhelmed the Border Patrol in the Rio Grande Valley that officials have transported more than 750 children since last week to Border Patrol facilities in Arizona — with plans to bring hundreds more, if necessary.

Calling the situation "a humanitarian crisis," President Barack Obama has sent federal officials scrambling to ramp up temporary housing in three other states for about 3,000 more migrant children.

Reports suggest Monday that at least 1,100 immigrant children are being held by the U.S. Border Patrol in Nogales, and more are expected as children continue to cross the Mexican border in Texas.

Here are the key questions and answers about what is happening and why:

How many unaccompanied children are crossing?

According to Customs and Border Protection, in the past eight months, agents have apprehended about 47,000 unaccompanied minors who crossed the border into the U.S. illegally from Mexico.

The CBP estimates that apprehensions of minors this year may reach 90,000.

Almost three-fourths of the children apprehended are from Honduras, Guatemala or El Salvador. And 33,470 of them entered through the Rio Grande Valley Sector, which this year surpassed the Tucson Sector as the busiest for illegal crossings. Overall, Border Patrol apprehensions of undocumented migrants are still running at less than half of the rate of 2000-06, when they typically exceeded 1million a year.

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Why are so many children crossing now?

Gang violence in El Salvador and in urban areas of Guatemala has escalated dramatically in recent months since a weak truce among rival gangs has evaporated, said Elizabeth G. Kennedy, a Fulbright scholar reached Monday in San Salvador, the capital of El Salvador.

"Half of them are fleeing for their lives," she said.

Kennedy, investigating the causes of child migration, has interviewed more than 400 child migrants. For many, Kennedy said, "their decision is: Do I face possible death in migrating or sure death in staying?"

The gang violence "particularly affects youths," said Alison Ramirez, who works on a U.S.-funded violence-prevention project in El Salvador and who frequently visits Honduras and Guatemala.

"The gangs are in schools, neighborhoods. They're everywhere," she said. "Even if the kids don't want to be a part of it, they get caught up in the crossfire, extorted, threatened."

"The violence is one of the drivers in Honduras," said David Scott FitzGerald, associate director of the Center for Comparative Immigration Studies in California. "Just looking at the homicide rate, it has tripled in the last decade. It's the highest in the world for a country not at war."

Children from Honduras, Guatemala and El Salvador aren't just fleeing to the United States. Increasing numbers have been seeking asylum in Mexico, Costa Rica, Panama, Nicaragua and Belize, according to the U.N. High Commissioner for Refugees. Kennedy and Ramirez agreed that most children who flee to the United States do so because they have family members here.

The family ties are a key factor, too, said Cecilia Menjivar, a sociologist at Arizona State University who has researched migration from Central America for more than 16years.

"Immigration laws have as much to do with the crisis as the conditions back home," she said.

She said that because of civil war and post-conflict violence, Hondurans have been able to seek asylum and be granted temporary protected status since 1998. Salvadorans have been able to gain temporary protected status since an arthquake in 2001.

That status doesn't allow holders to gain permanent residency, but they are allowed to work.

"A lot of people who have that status have children they haven't seen in a long time," Menjivar said. "That means they may be encouraging their family members to take the dangerous journey north even as children are motivated to flee violence or seek better economic opportunities."

Why are they being sent to Arizona?

Capacity. For most of the past decade, the Tucson Sector has been the busiest in the country for illegal border crossings, Border Patrol spokesman Andy Adame said.

As a result, the sector "has gotten a lot of resources in terms of agents, infrastructure and technology," he said. "And we have two big processing facilities, in Nogales and Tucson."

It's important to note that the unaccompanied children being sent to Arizona won't stay here indefinitely. In a telephone conference Monday, White House officials agreed to discuss what the administration is doing so long as they were identified only as "senior administration officials."

They said the goal — not yet being met — is to process each minor within 72hours either to be turned over to Immigration and Customs Enforcement for deportation proceedings or to the Health and Human Services Department to be reunited with family members or placed in foster homes pending deportation proceedings.

The Nogales, Ariz., holding facility received mattresses and four portable showers over the weekend. The Border Patrol didn't respond by deadline to questions about whether additional showers and other supplies had been delivered Monday.

Can't the Border Patrol just stop them?

The short answer: No. While the U.S. government has spent more than $126billion over the past nine years on border security and enforcement, much of the fencing and infrastructure was built in California, Arizona and western Texas, which were the major crossing areas over the past decade.

The Border Patrol has been moving increasing numbers of agents into the Rio Grande Valley Sector, but vast stretches of the river are easy to cross, and there is extensive vegetation along the banks that makes it easy to hide both before and after crossing.

What is the Obama administration doing about the children?

Senior administration officials said Monday that they had been preparing for increased numbers of unaccompanied children but that the numbers have been much greater than they expected.

Officials said they have been in daily contact with the governments of Mexico, Honduras, Guatemala and El Salvador and carrying out public-information campaigns in those countries to warn people of the dangers children face and that they are not eligible for any kind of residency or protected status under any potential immigration-reform measure.

The administration last week named a team, led by W. Craig Fugate, administrator of the Federal Emergency Management Agency, to coordinate with Homeland Security on how to handle the massive influx of unaccompanied minors.

Federal officials said they are working to improve the conditions in the Nogales processing facility. As of Monday, they had also readied facilities to temporarily house up to 1,767 children at military bases in California and Texas, and they were preparing additional temporary housing at Fort Sill, Okla.

Depending on how many minors Border Patrol agents continue to apprehend in Texas, more children may be sent to Arizona, officials said.