A retired veteran hired to work security for migrants being bused out of Texas alleges he witnessed pervasive mistreatment during the long trips to other cities.

David Dillard claims he saw migrants being misled about their destinations amid "disgusting and inhuman" conditions on board. He also claims he received an email that directed him to stop communicating with nongovernmental organizations (NGOs) seeking to coordinate assistance for the migrants.

“This job, from Day One, was never meant to be done the right way. The job meant from Day One was just to get people on a bus and out of Texas. That's it. They didn't care about their health. They didn't care about where they were going,” Dillard told ABC News.

More than 50,000 asylum seekers have been bused from Texas to mainly Democratic-led cities since April of last year as part of Gov. Greg Abbott’s Operation Lone Star.

The state of Texas tapped bus company Wynne Transportation to handle the project for more than $100 million. Wynne Transportation then hired security firm Mayhem Solutions, which brought on Dillard as a contractor.

Dillard, who served in the U.S. Army, says he holds “Republican values” and at first supported the busing of migrants out of Texas. But he says he had a change of heart after being hired.

“I started asking questions and the questions were not meshing at all with reality. At that point, I remember texting a friend of mine saying, ‘I'm only staying here because I want to make sure that the migrants get treated right.’ Because there were migrants who were getting yelled at, told no, weren't no stops being made. They cannot stop in Texas. Those migrants, once they're on the bus, they're getting out of Texas,” Dillard said.

Getting the buses out of Texas, the second largest state in the U.S., would take anywhere from seven to 12 hours, depending on the destination, Dillard said.

“You got one bathroom and the bathroom, you cannot have No. 2, you can only use for No. 1, but you got women's tampons, babies’ diapers, everything in that one bathroom. It'll start overflowing and leaking down the thing. We tell them, stop using it after that,” Dillard said.

Dillard says photos he took show urine running down the aisles of the bus, calling it “disgusting and inhuman.”

Dillard said he was involved with “well over 100” bus trips and at one time was making up to $450 per day for the job.

NGO representatives in Texas help process migrants who have chosen to board Operation Lone Star buses and coordinate with groups in destination cities to meet them when they arrive. The state does not get involved in that coordination effort.

Dillard says he initially would let the NGOs know how many migrants were on board the buses and when they would arrive at their destination. But suddenly, in August 2022, Dillard says he and other contractors were told via email to stop speaking or coordinating with the NGOs altogether.

According to an email provided by Dillard, Mayhem Solutions manager Bryan Smith also said the state wouldn’t be sharing information with aid organizations going forward, either.

The email also instructed staff to keep bus numbers and identifying information hidden from sight, including from the passengers themselves.

Smith has not responded to ABC News’ request for comment.

Dillard also claims he was instructed to stop letting passengers use his Wi-Fi hotspot on the bus, “because they found out the migrants were using their phones to figure out where they're at.”

In a statement to ABC News, the Texas Division of Emergency Management said it is “not aware of any directive to remove Wi-Fi service on any bus” or “any effort to conceal the identifying bus numbers.”

Dillard says he was on one of the buses going to Washington, D.C., on Sept. 14, 2022, when Wynne Transportation personnel instructed him to wait overnight in a parking lot for another bus to catch up with him, because they wanted to drop off the migrants in front of Vice President Kamala Harris' home.

“Abbott coordinated the whole thing just to say F-you to the VP. That’s petty politics of people’s lives. It’s inhuman, man,” Dillard said.

Abbott tweeted later that day, “We’re sending migrants to her backyard to call on the Biden administration to do its job & secure the border.”

A spokesperson for Abbott told ABC News the governor's office was “not aware of directives” to either stop communicating with NGOs or coordinating the drop-off at the vice president's home.

Wynne Transportation referred all questions to the state’s emergency management agency, which told ABC News that migrants sign waivers consenting to their destinations.

Meanwhile, Dillard says that all the hours spent on the buses changed his view on those coming to the U.S. in search of a better life.

“We went around a corner and the White House was on the left, and I said, ‘Hey, there’s the White House.’ And then went down, I said, ‘There’s the Washington Monument right there,’” Dillard said.

Dillard continued, “And they started clapping and crying. People were hugging. And as from a U.S. soldier standpoint, that's why I do this. That right there. They were more American in that moment than I'd ever been in my entire life. And that was the greatest feeling in the world.”

Dillard says he was eventually terminated after a pay dispute with his supervisor and says he can’t get work as a result.

When asked what he’d say to being called a “disgruntled employee,” Dillard said, “Not at all. I am disgruntled in the fact that people were treated, [how] humans were treated on my watch.”

“These people deserve not to be pawns,” Dillard said.

ABC News' Lena Jakobsson contributed to this report.