I'm Lester Holt, tonight on Date Line. A black life ends in a struggle with white police officers.

There was a cry for help and a video. Sound familiar? The heartbreaking and important story of Anton Black.

I can't sleep to this day. I see him begging for the life. He was George Floyd before George Floyd.

He told our mother that he loved her. No mother should have to witness what you witness.

He didn't attack nobody, he didn't rob a bank, he didn't kill nobody. That's not it right?

Everything seems to escalate. I'm teasing him. I'm curious how many times you've used your taser as a police officer?

No. Just don't tease people. You'll see any indication of malice. I'll see any indication of indifference.

He needs help. I really felt like it was a professional response.

From a medical examiner's point of view, this was no accident. It's death at the hands of another. That's a homicide.

I want the truth to be known about my brother.

What happened to Anton Black?

It was Saturday evening, September 15, 2018 in the small quiet town of Greensboro, Maryland. Around 7pm, Dinees Salah and her husband Tony were driving home from church.

We could see these small cars on the street.

It was Saturday evening, September 15, 2018 in the small quiet town of Greensboro, Maryland.

Around 7pm, Dinees Salah and her husband Tony were driving home from church.

We could see these two black boys. The bigger boy had the smaller boy in a headlock.

He put the full Nelson, picked him up, swung him.

This definitely was not worse.

At that point, did you want him to keep them in your sight?

Yes. Dinees and the younger boy locked eyes.

And I said, are you alright? No, he said.

So you dialed up 911.

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