Donald Trump toured the U.S. and Mexico border on Thursday to better understand the issues surrounding the area that has garnered him criticism from Hispanic groups and opponents.

The New York real estate mogul wore a hat with the slogan "Make America Great Again" as he exited his 757 that landed in Laredo, Texas, a city with a 96 percent Latino population, reports USA Today. He was greeted by protesters -- one demonstrator held a sign that read, "McCain is a hero, Trump is a chump."

Trump toured the border but not with border patrol agents, whose union said members would not accompany him because the visit was "too politicized."

"Local 2455 does not endorse candidates for any political office," said Hector Garza, president of Local 2455 of the National Border Patrol Council, in a statement.

According to Trump, border agents invited him to tour the border to show him "the tremendous problems" and "the tremendous crime" they deal with on a daily basis. He accused Washington, D.C., superiors of silencing them before his visit.

From his tour, Trump seemed to draw the conclusion the current border fence is not entirely secure.

"There is a huge problem with the illegals coming through," Trump said. "In certain sections, you have to have a wall."

Garza agreed with Trump's observation.

"Make no mistake, our border with Mexico is not secure, and there's no doubt we need to have an honest discussion about that with the American people," Garza said.

Once the tour concluded, the businessman held a news conference in which he pledged to secure trade deals with Mexico, China and other worldwide competitors.

"I'll bring those jobs back, and the Hispanics are going to get those jobs," Trump said.

Laredo Mayor Pete Saenz stood next to Trump during the conference but did not endorse him. Saenz said better immigration enforcement is needed in the nation, along with a comprehensive overhaul.

Rep. Joaquin Castro, D-Texas, criticized Laredo elected officials for engaging with the 2016 Republican presidential candidate during his visit.

"Donald Trump just used you and the other council members to make him look good," Castro wrote on Twitter Thursday. "Embarrassing for South Texas and Hispanics."

Trump thanked Laredo officials for touring with his motorcade. "We were treated so nicely," he said. "We learned so much."

Despite his remarks that Mexico sends "criminals" and "rapists" across the U.S. border and provocations that have frustrated many in the Republican Party, Trump is leading in recent national polls.