We're talking a lot about the prosecution and the defence.

The prosecution is being brought by the state of Minnesota and arguing the case against former officer Derek Chauvin. Minnesota Attorney General Keith Ellison is leading the state's prosecution, but he has yet to speak in court during the trial. So far Jerry Blackwell and Matthew Frank have led the opening arguments and questioning of witnesses.

The defence is tasked with representing Derek Chauvin. Eric Nelson, an attorney who has represented several police officers in the past, has been the only lawyer to speak on behalf of Chauvin's defence so far. There are nearly a dozen other lawyers working behind the scenes, but none have so far appeared in court.

Lebo Diseko
BBC News, Minneapolis

The jurors took their morning break after powerful testimony from a now 18-year-old witness who was a minor at the time of the incident.

It was her mobile phone video of Derek Chauvin kneeling on George Floyd’s neck that was seen around the world.

Asked why she started filming, the witness said: “I saw a man terrified, begging for his life. It wasn’t right – he was in pain."

She described hearing George Floyd “saying 'I can’t breathe'. He was terrified, he was calling for his mom.”

The prosecution is trying to tell this story through the eyes of the people who were there at the time.

Prosecutor Jerry Blackwell asked her if she saw Chauvin do anything to administer care to Floyd and she said “no”. She said it looked like Chauvin was feeding off the energy of the surrounding crowd and “shoving his knee into his neck” even more.

Eric Nelson, Derek Chauvin's defence attorney, is back up. He is now questioning Darnella, the 18-year-old eyewitness to George Floyd's arrest who took the viral video.

Image source, Court TV

Prosecutor Jerry Blackwell's questions to Darnella are challenging the defence's suggestion that the bystanders watching George Floyd that day were an "unruly mob".

"Did any other bystanders threaten the police," Blackwell asks. "Did any of them ever get violent with the police?"

"No," Darnella responds to both.

"Did you see violence?" the prosecutor asks.

"Yes, from the cops," Darnella replies. "From Chauvin, and from Officer Thao," another police officer present that day who will face trial on a later date.

"Did you feel threatened by the police officers?"

"Yes," Darnella says - noting that Officer Thao had put his hand on his pepper spray, poised to use it.

After a recess, Blackwell asks if Chauvin's behaviour changed in "response" to the crowd watching him.

"Did you see him kneel harder [on Floyd's neck] in response?" Blackwell asks.

"Yes," Darnella responds.

According to Darnella, Chauvin did not remove his knee from Floyd's neck until he was instructed to do so by a paramedic.

The morning break is over, and the examination of witnesses is continuing.

Darnella, an 18-year-old who the court has ruled can only be identified by her first name and is not shown on camera, is on the witness stand.

She filmed the video of Floyd's arrest that was seen around the world.

Barbara Plett Usher
BBC News, Minneapolis

One of the most vocal bystanders was Donald Williams, who says he was trained in mixed martial arts.

He told the prosecution he believed he’d witnessed a murder and placed a call to 911 – in effect calling the police on the police.

In earlier testimony he said that Chauvin was using a dangerous technique called a “blood choke” and that the former police officer was moving his knee back and forth to increase the pressure.

This is important for the prosecution’s case that the use of force was the primary cause of death.

The defence will argue that it was a combination of a drug overdose and Floyd’s poor health.

The judge has just announced a 20 minute break.

When they return, we expect more questions for 18-year-old Darnella, who filmed the viral video of Floyd's arrest.

Donald Williams was a bystander who witnessed the death of George Floyd and delivered gripping testimony on the stand over the past two days.

Social media users are praising Williams for keeping his cool under questioning.

Many also criticised the defence team for trying to paint him as an "angry black man" interfering with the officer's work to arrest Floyd.

Image source, Court TV

"Sounds like you've got a nice loud voice and we'll be able to hear you at the microphone," says the judge as the first young witness is introduced.

Darnella turned 18 last week and is still in high school, she says.

She describes walking from her house to nearby Cup Foods - something she's done "hundreds or even thousand of times".

She was with her young cousin on the day of Floyd's arrest "to get some snacks", she says.

Darnella was the teenager who filmed Floyd's arrest in a video that was widely shared around the world.

Samantha Granville
BBC News, Minneapolis

Yesterday there were hundreds of journalists outside the courthouse in Hennepin County. We were all piled on top of each other - some on the ground, some of us holding a squat for almost an hour - as we all fought to get pictures of George Floyd’s family.

Today, however, there were less than a dozen. It’s just as cold, but incredibly quiet. We didn’t hear or see the legal team before court was called to order. A few protestors have gathered outside, with signs that say Black Lives Matter.

Earlier this morning, Judge Peter Cahill issued a ruling on a motion regarding the filming of witnesses on the stand who were under 18 at the time of Floyd's arrest.

The state has requested that cameras be switched off for underage witnesses such as Darnella, the 17-year-old who filmed Floyd's arrest in the video that went viral.

The media coalition who are reporting the trial have opposed the state's request.

The judge ruled that their video will not be shown, but audio will be permitted.

A lawyer for Darnella told the BBC last year that the decision to film Floyd's arrest traumatised her.

Defence lawyer Eric Nelson asks: "When you were engaged in mixed martial arts, in competitive fights, where you able to have a conversation with your opponent?"

Williams responds: "We didn't talk to each other, so no."

Prosecutor Matthew Frank then asks whether fights end when an opponent "taps out".

Williams says yes, and then is excused for the day.

The defence team has ended their questioning of Williams. Before they let him off the stand, the prosecution has more questions about his experience as a fighter.

"Do you ever have a situation where an opponent ever is handcuffed behind his back," asks Matthew Franks.

"Never," chuckles Williams, a professional MMA fighter.

The prosecutor asks if he's ever been in an MMA fight that is three against one.

No, responds Williams.

When asked about when opponents go unconscious during fights, Williams says medical attention is provided "immediately, right away".

Referring to his experience as a security guard, Franks asks if there are non-physical ways to end conflicts.

Williams says there are plenty of de-escalation techniques.

"Stay calm, being humane, trying to talk to the person, trying to talk them down," says Williams.

Defence lawyer Nelson is now reading out Williams' insults to the police that he said during Floyd's arrest, that were caught on bystander video.

"You called him a tough guy," says Nelson.

"You watched the video," fires back Williams.

"You called them a real man," says Nelson.

"You watched the video," repeats Williams.

The judge then intervenes to tell Williams that he is required to answer the questions "yes or no".

"You called them a bum at least 13 times," continues Nelson.

"That's what you count in the video? Then that's what you got," says Williams.

Asked whether he was growing "more and more angry" in the moment, Williams pushes back.

He says his words "grew more and more pleading for life", as Floyd went unconscious.

"It's fair to say you grew angrier and angrier?" asks Nelson.

"No, I grew professional. You can't paint me out to be angry," Williams replies.

Chauvin's defence lawyer has been asking a series of questions about fight moves for the last twenty minutes.

Here's a sample of some of the questions he's been asking Donald Williams, a professional fighter and bar bouncer, who witnessed Floyd's death:

• How important are weight classes in wrestling competitions?
• Do some forms of chokehold protect the trachea?
• Have you ever seen someone get knocked out, then get right back up and continue fighting?
• Have you ever had to deal with a crowd of people that is upset?

Williams answers "that is correct" to most questions and at other times clarifies wrestling moves and terms, as well as clarifies his professional experience. Nelson also asks for William's record as a fighter.

Prosecutors have no further questions for Williams, so now it's defence lawyer Eric Nelson's turn to question him.

He begins by asking questions about wrestling and "using your bodyweight", since Williams himself is a professional mixed martial arts fighter - and previously criticised the chokehold Chauvin used on Floyd.

Nelson asks: "The notion of a chokehold is very common within the martial arts community?"

Williams says yes, it is.

Nelson goes on to say there are several types of chokeholds, including a "rear naked choke" and others.

Nelson is now asking about weight divisions in tournaments and how fighters' weights can impact who they compete against.

Image source, Court TV

The prosecution is playing the call for the jury that Williams made to the police about the treatment of Floyd during his arrest.

You can hear Williams frantically telling the police dispatcher that an officer placed his knee on Floyd's neck, even when he became unresponsive.

"I was very lost in the moment, I was very nervous and not knowing what to do," Williams told the court.

"I did call the police on the police," he says.

Williams is heard throughout the bystander video imploring the police to let Floyd breathe. He is also repeatedly heard calling officers "punks" and using profanity.

The defence is now questioning Williams.

Image source, Court TV

Asked why he didn't directly interfere in Floyd's arrest, Williams says one of the officers prevented him from approaching.

"I did as much as I could," he says, adding that he was being forced to stay out of the street.

He says another bystander there, who identified herself as a medical emergency worker, asked repeatedly if she could check Floyd's pulse.

"Did you hear anyone threaten the safety of the officers?" asks the prosecutor.

"No I did not," he says. One man who Williams says was obviously upset, went back into the store after he told him to.

He said the man was crying when he went back inside, and never made any moves toward police officers.

Judge Cahill is not wasting any time. The members of the jury have been seated and will hear further testimony from witness Donald Williams.

Floyd was "going through tremendous pain" Williams says, when asked to explain what he saw.

"You could see his eyes slowly rolling back in his head."

The second day of Derek Chauvin's trial has just begun.