Trump took the stage in Prairie du Chien, Wisconsin, on Saturday, one day after Harris made a rare visit to the Arizona-Mexico border. 

The former president, who has repeatedly made personal jabs at his Democratic opponent since she launched her presidential campaign this summer, used the rally to make false accusations about Harris’s mental capacity. 

“Joe Biden became mentally impaired,” Trump said. “Kamala was born that way. She was born that way. And if you think about it, only a mentally disabled person could have allowed this to happen to our country. Anybody would know this.”

The remarks swiftly garnered criticism from advocacy groups, including the American Association of People with Disabilities. 

Maria Town, the CEO and president of the group, said to the Washington Post that Trump has “inaccurate, hateful biases” against those with disabilities, adding that his remarks say more about him than his opponent. 

“Trump holds the ableist, false belief that if a person has a disability, they are less human and less worthy of dignity,” Town told the outlet. “These perceptions are incorrect, and are harmful to people with disabilities.”

Since President Joe Biden suspended his presidential campaign, paving the way for Harris to take his place, Trump has levied a number of personal attacks against Harris. Most notably, the former president questioned Harris’s racial identity. 

During the Wisconsin rally, Trump also took time to slam the administration’s response to the border crisis, alleging Harris was “erasing our border.” 

“I will liberate Wisconsin from the mass migrant invasion,” Trump reportedly said. “We’re going to liberate the country.”

He went on to call undocumented immigrants that have committed violent crimes “monsters,” “stone-cold killers,” and “vile animals,” according to Reuters. 

Trump continued his anti-immigration rant, accusing some immigrants of wanting to “rape, pillage, thieve, plunder and kill the people of the Untied States of America.” 

Saturday’s rally took place in Prairie du Chien, where there have been reports that earlier this month an immigrant in the U.S. illegally affiliated with a Venezuelan gang was arrested after assaulting a mother and daughter.

As Trump issued the harsh allegations, he admitted he was giving “a dark speech.” 

Following the rally, Harris spokesperson Sarafina Chitika agreed with that characterization telling Reuters, “He’s got nothing ‘inspiring’ to offer the American people, just darkness.”