Sen. J.D. Vance on Sunday doubled down on former President Donald Trump's claims that members of the Venezuelan Tren de Aragua gang have "overrun" the city of Aurora, Colorado, saying Mayor Mike Coffman has admitted there is a problem while denying one exists.

"Well, Martha, you just said the mayor said they were exaggerated," Trump's running mate told ABC News' "This Week" anchor Martha Raddatz. "That means there's got to be some element of truth here."

Coffman, the GOP mayor of Aurora, said Trump's claims, made during a rally in the city and during other political speeches and interviews, are "grossly exaggerated" and that they "have unfairly hurt the city's identity and sense of safety."

During a rally Friday in Aurora, located near Denver, Trump repeated claims that the migrants have "invaded and conquered" the city and accused his Democrat rival, Vice President Kamala Harris, of letting the city's buildings be "infested" by gang members, calling them "animals and barbaric thugs."

He also unveiled a plan he's calling "Operation Aurora" and promised that if he's elected, "we will send elite squads of ICE [Immigration and Customs Enforcement], Border Patrol, and federal law enforcement officers to hunt down and arrest and deport every last illegal alien gang member until there is not a single one left in this country."

Raddatz told Vance that the city says the issues are limited to a few apartment complexes and that the mayor said the city's police will handle the concerns.

But Vance argued that Harris has caused the issues in Aurora through her involvement with the Biden administration and as its "border czar."

"Unfortunately, when you let people in by the millions — most of whom are unvetted, most of whom you don't know who they really are — you're going to have problems like this," he said, adding that Harris "bragged about opening the border, and now we have the consequences, and we're living with it."

"We're not going to do better, Martha, unless Donald Trump calls this stuff out. I'm glad that he did," said Vance.

The Ohio Republican also defended Trump's claims that aid from the Federal Emergency Management Agency that should be going to hurricane victims in Florida, North Carolina, and Georgia has instead gone to migrants.

"What the president said is that, fundamentally, FEMA aid is distracted by going to illegal migrants," Vance said. "We've got Republican congressmen who are on the ground who represent that area saying that they have to call the White House to get food and water to FEMA."

Vance said that he doesn't think there is "anything malicious" happening," but at the same time, "we've had an incompetent response to this particular crisis, particularly in western North Carolina, which, to be fair, was hit harder than a lot of us expected it."

Raddatz on Sunday also asked Vance if Trump plans to go after his political opponent if he wins the November election.

"No, he was president for four years, and he didn't go after his political opponents," said Vance, claiming instead that Harris has "tried to arrest everything from pro-life activists to her political opponents."

Raddatz told Vance that Trump has threatened to prosecute people who have cheated in the election, and he responded that the former president has said that "people who violated our election laws will be prosecuted."

"I think that's the administration of law," he added. "He didn't say people are going to go to jail because they disagree with me."

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