South Dakota Gov. Kristi Noem opened the third night of the 2020 Republican National Convention by painting a dark portrait of American cities amid the widespread unrest and violence gripping many of them following the death of George Floyd in Minneapolis police custody and, more recently, the police shooting of Jacob Blake in Kenosha, Wis.

The cases of both Black men fueled allegations of police brutality and racial injustice, and protests have escalated into looting and violence in many places. Singling out cities like Portland and New York, Noem decried what she called cities “overrun by violent mobs” and heaped blame on “Democrats and their radical supporters.”

“It took 244 years to build this great nation,” Noem said in a pre-recorded speech from the Mellon Auditorium in Washington, D.C. “But we stand to lose it in a tiny fraction of that time if we continue down the path taken by the Democrats and their radical supporters.”

Noem added: “Democrat-run cities across this country are being overrun by violent mobs. The violence is rampant. There’s looting, chaos, destruction, and murder.”

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The South Dakota governor’s words come as Trump and his supporters have stuck to a firm law-and-order message during the convention, warning that electing Democratic presidential nominee Joe Biden would lead to violence in American cities spilling into the suburbs. Trump on Wednesday tweeted about sending federal agents to Kenosha to help quell unrest, and the Justice Department said it was sending in the FBI and federal marshals.

“In just four years, President Trump has lifted people of all races and backgrounds out of poverty,” Noem said. “He shrunk government and put money back into the pockets of hardworking, ordinary Americans. He has advanced religious liberty and protected the Second Amendment. You can look back 50 years, and you won’t find anyone that has surpassed President Trump’s success on these four issues alone.”

Noem, a close ally of Trump, has been fiercely critical of the unrest gripping cities across the nation and the surge in violent crime in many urban areas — telling Fox News earlier on Wednesday that if Trump is not reelected, the alternative will be more violence and turbulence.

"There is no mother in this country that wants to raise her children on the streets of Portland, Seattle or Washington," Noem said.

KENOSHA VIOLENCE: 3 SHOT, INCLUDING 2 FATALLY IN ANOTHER NIGHT OF UNREST 

The raging protests in Wisconsin this week are in response to the shooting of Blake, 29. Kenosha police have said little about what happened other than that they were responding to a domestic dispute, but state agents later recovered a knife from the driver’s side floorboard of the vehicle.

Wisconsin Gov. Tony Evers has authorized the deployment of 500 members of the National Guard to Kenosha, doubling the number of troops. The governor's office said he is working with other states to bring in additional National Guard members and law officers. Authorities also announced a 7 p.m. curfew, an hour earlier than the night before.

Trump’s Justice Department is sending in more than 200 federal agents from the FBI, U.S. Marshals Service and the Bureau of Alcohol, Tobacco, Firearms and Explosives in response to the unrest. The White House said up to 2,000 National Guard troops would be made available.

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Biden posted a video saying he had spoken with Blake's parents and other family members.

“What I saw on that video makes me sick,” Biden said. “Once again, a Black man, Jacob Blake, has been shot by the police in broad daylight, with the whole world watching.”

The GOP’s convention response to the unrest has been uneven. The lineup of speakers has included men and women who have been at odds with the Black Lives Matter movement, including a St. Louis couple who brandished guns and the Kentucky attorney general who has not yet filed charges in the death of a woman killed by police in his state earlier this year.

The party, however, has had a number of prominent African Americans speak, including South Carolina Sen. Tim Scott, former NFL star Herschel Walker and Democratic Georgia state Rep. Vernon Jones.

The Associated Press contributed to this report.