Transcript for Trump's Homeland Security Secretary Details Mexican Border Trip
The new homeland security secretary, John Kelly, paying a visit to the Mexican border. Our Jim Avila injoed him for a look at the underground tunnels in California that reportedly are used by drug smugglers. All of this as federal agents hold immigration raids across the country. Reporter: Is this the deportation force candidate Donald Trump spoke of in his campaign for president? Across the U.S. And several major American cities, ISIS agents are conducting what they call a surge, picking up and deporting undocumented immigrants with criminal records including mothers and fathers who have raised children here. They called me in at 7:00 A.M. Telling me that my father was being deported and he got captured. Reporter: Immigration groups claim the criminal records include nonviolent felonies such as fake social security cards, and DUIs where no one was injured but the new homeland security secretary-general John Kelly who accompanied ISIS agents on raids Friday in San Diego before touring a border tunnel told me everyone deported deserved it. Are those the bad ombres that the president you and he feel need to be returned to Mexico. After being picked up and ported they're the right people. The men and women of ISIS and homeland security are doing it legally. Reporter: He defends the price of the border wall now estimated between $0 billion to $25 billion in an internal homeland security document seen by reuters. Are you convinced that it's still of value, taxpayers will get their money's worth with a wall. I don't know what the alternative is. The drugs alone are costing Americans $250 billion a year. Reporter: Worth it, Kelly says, even though a wall will not deter the tunnels dug beneath. This tum is about 90 feet deep and about 4 football fields long. Now, I'm 6 feet tall and I can nearly stand up straight in it. No single wall will -- physical barrier will stop everything. It's got to be backed up by people. Reporter: The trump administration delivering on its promise to crack down on illegal immigration even if it's expensive and even if it splits families living here for years. For "Good morning America," Jim Avila, ABC news, along the border in southern California. Fascinating, Jim, thank you.
This transcript has been automatically generated and may not be 100% accurate.