Shifting our focus now to a gruesome murder in Charlotte, North Carolina last month that claimed the life of a young Ukrainian refugee and has become a rallying cry for Republicans.

They argue Democrats are soft on crime and they point to the killing to support President Trump's decision to deploy the National Guard in more cities.

Our William Brigham has the latest.

The security camera video from the Charlotte Light Rail System is very hard to watch, and we are not going to show it in full.

23-year-old Arena Zarutska boards a train after work and takes a seat.

Behind her in the red hoodie is to Carlos Brown Jr., who authorities say was homeless and mentally ill.

Brown opens a pocket knife, gets up, and stabs Zarutzka in the neck.

She had fled Ukraine after Russia's invasion and settled in North Carolina.

She died on the spot.

Brown was charged in federal court today.

According to authorities, he had previously spent time in prison for robbery

and had repeatedly shown troubling erratic behavior,

from attacking and biting his sister to calling police,

saying he was being controlled by some man-made substance.

His mother told local news that he was schizophrenic.

This horrible crime has now been seized on by Republicans to depict Democratic-run cities like

Charlotte as being plagued by widespread violence and mayhem.

Charlotte's police say violent crime so far this year is down 25 percent compared to last year.

Many Republicans all the way up to the president have blamed Democrats for this murder. President

Trump posted this today. For far too long, Americans have been forced to put up with Democrat-run cities that set loose savage,

bloodthirsty criminals to prey on innocent people.

For more on this case, we are joined by writer Elisa Roth.

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