A retired Border Patrol chief tapped to advise on immigration issues related to unaccompanied minors and refugees for the Trump administration's first 100 days said about 70% of sponsors' applications were fraudulent.Chris Clem, who spent almost three decades with Customs and Border Protection, says the Trump team is working to resolve the many problems created by nearly 470,000 unaccompanied children crossing into the United States over the last four years, "overwhelming a system that was really put in place to protect the well-being and welfare of children.""It actually pretty much did the opposite with so many because the system was broken, the policies and practices were broken, where children were being placed [with] sponsors that were unvetted or improperly vetted or may have been illegal aliens themselves or smugglers or criminals," Clem, who was based out of Yuma, Arizona, during the Biden administration, told Fox News Digital. "So, my role was to go in there with my 27-plus years of Border Patrol experience, and having dealt with this firsthand in the field for years, to rebuild and put commonsense practices and policies in place. And that's what we did."Clem worked with President Donald Trump's Health and Human Services Department to improve the vetting of documentation from sponsors offering to take in unaccompanied minors.MIGRANT SEX TRAFFICKING SURVIVOR SPEAKS OUT: 'I SAW GOOD PEOPLE DIE'They are also working to identify and arrest criminals who provided fake documentation to become sponsors."Here's an example we'll call it the Ohio case, where a sponsor claimed to be an adult brother of a 14-year-old female," Clem said. "He was accepted by ORR [the Office of Refugee Resettlement] and this happened a little over a year ago. There [were] other adults living there that should not have been placed with that person. Unfortunately, she was placed. The 14-year-old was raped and impregnated, and the sponsor ultimately was arrested."SMUGGLERS ABANDON TWO MIGRANT GIRLS AT SOUTHERN BORDER WITH NOTE TO AUTHORITIESThe federal government "chose not to pursue" fraud charges for the subject, who lied to federal agents about his documentation, but state prosecutors did, Clem said."That's how we were able to catch him and ultimately get him indicted federally for trafficking, for fraud, for lying to federal agents," Clem said. "And so this person is looking at a lengthy time."HOUSE REPUBLICANS GRILL HHS SECRETARY BECERRA OVER MIGRANT CHILDREN: 'WOULD NOT WANT TO BE YOU'The Justice Department documented the case in April, when federal officials were able to charge the suspect, Juan Tiul Xi, 26, of Guatemala."There are literally thousands of cases where there is assault, abuse," the former Border Patrol chief said. "We did an internal investigation and some random sampling where about 70% of the sponsor applications are fraudulent. Meaning there is information that is not verifiable, it's incorrect, the documents submitted were not valid, and yet they were placed."While trying to track down potentially fraudulent sponsors and criminals housing unaccompanied minors can be disturbing, Clem says various departments within the Trump administration are working every day to combat this kind of illegal activity occurring in the United States as a result of four years of an unsecured border.They are also bolstering border security: U.S. Customs and Border Protection said last week it averaged 279 apprehensions per day at the southern border in April, compared to 4,297 in April 2024. The total apprehensions for April this year landed at 8,383, compared with last year's 129,000.YOUNG SIBLINGS DISCOVERED WITH ADDRESS ON PIECE OF PAPER AMONG MASSIVE GROUP OF ILLEGALS AT BORDERCBP officials also noted that just five illegal aliens were temporarily released into the U.S. during April, compared to 68,000 during the same month last year."In Yuma, my last few months, we were averaging over a thousand arrests a day just in my little sector alone. They're averaging four arrests a day now," Clem said. "So, you can only imagine what it's like to be able to go out there and patrol and secure the border and not worry about threats getting away from you because you're actually able to go out there and arrest those or keep them from even coming in."TOM HOMAN ON 'FAULKNER FOCUS': 'I'VE NEVER BEEN MORE CONCERNED ABOUT THE SAFETY OF THIS COUNTRY'He noted that agents are also able to use their parking lot again. It had been covered by large tents to process the thousands of migrants passing through their sector every day under the Biden administration."What a time to be a Border Patrol agent, to be creative, innovative, go after targeted operations again, go after those that have eluded us, work side by side with state and federal law enforcement to go after threats that have already made it into the country," Clem said. "No. 1, they can do their job, and that's protecting America, and they sleep good at night knowing that they can give their all, and they're going to be championed by the White House as opposed to demonized by the White House."Clem expressed concern that some U.S. officials, including politicians, judges and attorneys or prosecutors, are using their government positions to protect illegal immigrants. He has a message for those people."We are going to leave no stone unturned. If you are complicit, if you are knowingly and willingly encouraging, aiding and abetting, directly or indirectly, illegal immigration, whether it's cross-border or inside the United States, we're coming after you," he said. "Those are the laws. And it doesn't matter if you are a teenage smuggler on the Rio Grande or a sophisticated cartel or, unfortunately, an elected member of Congress or a state and local government if you are aiding and abetting, if you are facilitating illegal activity, the U.S. government is coming after you."CLICK HERE TO GET THE FOX NEWS APPThe CBP recorded the lowest southwest border crossings in history in March, with fewer apprehensions in the entire month than there were in the first two days of the month in 2024 under the Biden administration.Border Patrol apprehended a total of 7,181 illegal aliens attempting to cross the southern border between ports of entry in March. This constitutes a 14% decrease from February, when Border Patrol apprehended 8,346 aliens. More dramatically, it is a 95%decrease from the 137,473 aliens apprehended under the Biden administration in the same period in 2024.Fox News' Anders Hagstrom, Bill Melugin and Peter Pinedo contributed to this report.