Trump's rally in Erie, Pennsylvania on Sunday took on similar themes as an event a day earlier that he himself described as a "dark speech". He told a cheering crowd on Sunday that Harris was responsible for an "invasion" at the US-Mexico border and "she should be impeached and prosecuted for her actions".
"Crooked Joe Biden became mentally impaired," he said.
"Sad. But lying Kamala Harris, honestly, I believe she was born that way. There's something wrong with Kamala. And I just don't know what it is, but there is definitely something missing. And you know what, everybody knows it."
With just over a month until the election, Trump is intensifying his use of personal and offensive attacks, even as some Republicans say he would be better off sticking to the issues.
His suggestions that political enemies be prosecuted are particularly notable for their departure from norms in the US in which the justice system is supposed to be protected from political influence. In recent weeks, Trump has threatened prosecutions of Google for allegedly giving priority to "good stories" about Harris and Meta CEO Mark Zuckerberg.
Trump has long threatened legal action against his rivals, including President Joe Biden and his 2016 rival, Hillary Clinton. This month he vowed to jail those "involved in unscrupulous behaviour" this election, including election workers, lawyers, political operatives, donors, and voters, yet again attempting to sow doubt about the integrity of the election.
But he also has many legal problems of his own. He was convicted in May of falsifying business records in a hush money case in New York, with a sentencing scheduled for November 26. Two other cases are pending — a federal case for his alleged role in the January 6, 2021, insurrection, and a state case in Georgia for his efforts to overturn his 2020 loss there to Biden. Prosecutors are appealing a federal judge's dismissal of a case involving his handling of classified documents.
Trump argues federal and state prosecutors are targeting him for political reasons, though there is no evidence to suggest that is true. If he wins the election, Trump could potentially pardon himself on the federal cases or order the Justice Department to shut down their investigations of him.
On Sunday, he acknowledged he might lose in November: "If she wins, it's not going to be so pleasant for me, but I don't care."
Trump has derided Harris, the first Black woman and person of South Asian descent to lead a major party ticket, as "stupid," "weak," "dumb as a rock" and "lazy". His allies have pushed him publicly and privately to talk instead about the economy, immigration and other issues.
Harris has not commented on Trump's recent attacks but has said when asked about other comments that it was the " same old show. The same tired playbook we've heard for years with no plan on on how he would address the needs of the American people".
Donald Trump has derided Kamala Harris as "stupid," "weak," "dumb as a rock" and "lazy". (AP PHOTO)
At the rally in Erie, Trump said the "invasion" would end and deportations would begin if he took office.
"Thousands of migrants from the most dangerous countries are destroying the character of small towns and leaving local communities in anguish and in despair," he said, talking about communities in the battleground states of Wisconsin, Michigan and Pennsylvania.
In August, the GOP leader said he was "entitled" to personal attacks against Harris.
"As far as the personal attacks, I'm very angry at her because of what she's done to the country," he told a news conference then.
"I'm very angry at her that she would weaponise the justice system against me and other people, very angry at her. I think I'm entitled to personal attacks."
