A union of Border Patrol agents backed out of a meeting with Donald Trump hours before his scheduled visit to the southern border on Thursday. And some agents harbor lingering concerns about Trump's understanding of the issue of illegal immigration.

Local 2455, the division of the National Border Patrol Council in Laredo, Texas, announced it was canceling all events with Trump but did not offer a clear explanation as to why. The union's statement mentions it had no intention to endorse a presidential candidate. A Border Patrol agent belonging to Local 2455 declined to comment to the Washington Examiner, and the national council did not return requests for comment.

In a statement, the Trump campaign claimed national pressure had forced the local union to back out and said, "They are being silenced and are very unhappy about it." But the reality on the ground may be different than Trump's perception of it.

Not every agent is pleased with Trump's antics, and some do not think he understands the issue of border security. A Border Patrol agent in the San Diego, Calif., sector said he thinks Trump misunderstands the issue of immigration at a fundamental level.

"Whoever is helping him is really giving him bad information; he's rough around the edges," the border patrol agent said. "He hit the nail on the head in terms of illegal immigrants committing crimes in this country…[but] when he made the comment regarding rapists, and Mexico is sending us trash, he got it wrong."

The agent added that many immigration enforcement officers are veterans, and Trump's pejorative comments about Sen. John McCain's, R-Ariz., time in captivity were misguided.

Chris Cabrera, vice president of the NBPC local 3307 in the Rio Grande Valley, said he's not sure Trump understands the problems his sector faces on a regular basis. Central Americans, especially families and children, flooded the Rio Grande Valley last summer, which caused a crisis at the border.

"I think he realizes there's a problem, I don't know if he knows to what degree it is," Cabrera said. "I don't know if he's sensationalizing it a bit or if he actually understands it. … It seems like he's very serious about the issue, which is a good thing, but I don't know to what degree he knows [about it] or if it's a hot topic and he's just jumping on it."

Cabrera said he and his fellow agents would welcome anyone pursuing elected office to visit the southern border, but few do so. Of all the elected officials to visit the border, Cabrera said he was most impressed by Sen. Ron Johnson, R-Wis., the chairman of the Homeland Security and Governmental Affairs Committee.

Trump's rhetoric appears to have resonated with many voters, but some of those who live near the southern border still question his approach.

Linda Vickers, chief of staff of the Texas Border Volunteers, said she likes how Trump chooses to tell it like it is but disagrees with his tone. The Texas Border Volunteers is a group of people who assist law enforcement with securing the border.

"He [Trump] could do better with his wording and still be himself; what I'm not real keen on is his personal insults," Vickers said to the Examiner in an email. "Make no mistake, I do applaud Trump and would pick him for president over Hillary, Rubio, Bush, etc."

Vickers said she prefers Texas Sen. Ted Cruz for president because she trusts him.

Border Patrol agents across the southern border seem to appreciate the attention that Trump has brought to the southern border, but question his understanding of the issue. The Border Patrol union's decision to distance itself from Trump may coincide the lack of trust some agents have in his motivation.