Central American migrants pouring into Arizona city

PHOENIX — There has been a sharp rise in the number of Central American families and unaccompanied minors entering the country illegally along the border with Mexico in the Yuma area of southwestern Arizona, according to Border Patrol statistics.

That area had been one of the quietest areas for crossings along the entire southern border.

But the recent spike suggests smuggling organizations have changed their routes to evade stepped-up immigration enforcement in Mexico, sending Central American migrants through other areas of the border beyond south Texas.

The overall surge has created such crowded conditions at federal detention centers that U.S. immigration officials have been forced to released several hundred detainees from Haiti.

The Rio Grande Valley of south Texas remains the main entry point for a wave of Central American families and unaccompanied minors.

Temporary migrant processing center being built

The vast majority are from three countries: Honduras, El Salvador and Guatemala. Those countries are known as the Northern Triangle, where extreme gang violence has prompted many to flee, experts say.

The families are usually women with children. There also are still many minors traveling without parents. After entering the U.S. illegally, they typically turn themselves into Border Patrol agents in hopes of applying for asylum in the U.S.

The rise in Central American migrants arriving at the U.S. border contributed to an overall increase in apprehensions by the Border Patrol in fiscal year 2016 to 408,870 from 331,333, a 23% increase. Overall apprehensions, however, remain at levels not seen since the mid-1970s, according to Border Patrol statistics.

First major surge came in 2014

A surge of Central Americans in the late spring and early summer of 2014 overwhelmed the Border Patrol and created a humanitarian crisis for the United States. That mass migration was documented in an Arizona Republic series "Pipeline of Children."

The number of Central American families and minors dropped in fiscal year 2015. But there has been another big wave in 2016 on par with the one in 2014.

U.S. Customs and Border Patrol officials announced Thursday that a temporary detention facility is being built in Tornillo, southeast of El Paso, Texas, to help process the influx of Central American families and unaccompanied minors.

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The facility will open next week with room for up to 500 migrants. It's another indication of how Central American migrants arriving at the border are spreading to different locations.

Department of Homeland Security Secretary Jeh Johnson said earlier this month that there are about 41,000 people being held in immigration detention centers, about 10,000 more than usual, as a result of the recent rise in migrants along the southern border.

As a result, immigration-enforcement officials have begun freeing some Haitian migrants arriving in Arizona and California in response to the surge in border crossings.

Between Sept. 20 and Nov. 16, Immigration and Customs Enforcement released approximately 900 Haitian nationals because of the lack of detention space, according to ICE officials. Before their release, they were given paperwork instructing them to appear before an immigration judge. As of Nov. 12, 4,425 Haitian nationals remained in ICE custody.

Yasmeen Pitts-O'Keefe, an ICE spokeswoman in Phoenix, declined to say where the Haitian nationals were released.

She issued a written statement that said custody determinations are made on a case-by-case basis, "prioritizing serious criminal offenders and other individuals who pose a risk to national security or public safety."

El Paso has largest increase

The El Paso sector has seen the largest increase in family-member apprehensions, up 364% in fiscal year 2016, according to Border Patrol statistics. Apprehensions of unaccompanied minors in the El Paso sector rose 134% in fiscal year 2016.

In the Yuma sector, which covers the southwestern corner of Arizona and the southeastern corner of California, the Border Patrol apprehended 6,169 family members, most of them from Central America, in fiscal year 2016. That is a 256% increase from the 1,734 family members apprehended the year before, according to Border Patrol statistics. It's also up 814% from the 675 caught in fiscal year 2014.

The Border Patrol's Yuma sector also has seen a big spike in unaccompanied minors. Border Patrol agents in that area apprehended 3,266 minors in fiscal year 2016. That is up 200% from the 1,090 caught in fiscal year 2015 and up 830% from the 351 minors caught in fiscal year 2014, according to Border Patrol statistics.

In the Tucson sector, which stretches from the New Mexico line west to near Yuma, the Border Patrol caught 3,139 family members, and 6,302 unaccompanied minors in fiscal year 2016. That is a 7% and a 5% increase respectively, from fiscal year 2015.

Some more numbers:

• Border-wide, apprehensions of families are up 95% in fiscal year 2016, and apprehensions of minors are up 49%.

• The 77,674 family members apprehended border-wide in fiscal year 2016 exceeds the 68,445 caught in fiscal year 2014, the year of the surge.

• The 59,692 unaccompanied minors apprehended in 2016, however, fell below the 68,541 unaccompanied minors caught in 2014.

Some may be spurred by Trump

The rise in Central American migrants this year is primarily the result of an ongoing security crisis in the Northern Triangle countries, said Maureen Meyer, an expert on Latin American migration at the Washington Office on Latin America, a human-rights organization.

"We are increasingly hearing stories both at the U.S.-Mexico border and also from migrant shelters in Mexico of entire families that their lives are so much in danger that they pick up and take everybody and are looking for protection," she said.

Some also may have been spurred by President-elect Donald Trump's campaign promise to build a wall along the entire length of the border to stop illegal immigration from Mexico, she said.

"I certainly would not doubt that smugglers who have been very skilled at playing into people’s fears may have inspired some families to come now rather than later on," she said.

The spike in apprehensions of family members and unaccompanied minors in areas besides the Rio Grande Valley, including Yuma and El Paso, are signs that smugglers are finding new ways to evade Mexican immigration authorities, Meyer said.

Under pressure from the United States, the Mexican government increased immigration enforcement along its southern border with Guatemala along routes taken by Central American migrants, she said. That led to a drop in 2015 in the number of Central American migrants able to reach the United States by traveling though Mexico, she said.

The reason numbers are up again in 2016 is because so many people are leaving the Northern Triangle, and because smugglers have figured out ways of getting around Mexico's enforcement efforts, "either by developing new routes, or figuring out who to pay off," Meyer said.

Contributing: Aaron Martinez, El Paso Times. Follow Daniel González on Twitter: @azdangonzalez