MINNEAPOLIS - George Floyd's struggle with three police officers trying to arrest him, seen on body-camera video, included Floyd's panicky cries of “I'm sorry, I'm sorry” and “I'm claustrophobic!” as the officers tried to push Floyd into the back of a police SUV.

At one point, Floyd bucks forward, throwing his upper body out of the car. Officers eventually give up, and Floyd thanks them - and then is taken to the ground, facedown and handcuffed. Officer Derek Chauvin's knee pins his neck, another officer's knee his back and a third officer holds his legs, with the officers talking calmly about whether he might be on drugs.

“He wouldn't get out of the car. He just wasn't following instructions,” Officer Thomas Lane was recorded saying. The officer also asked twice if the officers should roll Floyd on his side, and later said he thinks Floyd is passing out. Another officer checked Floyd's wrist for a pulse and said he couldn't find one.

The officers' video was part of a mountain of footage and witness testimony Wednesday in Chauvin's trial on murder and manslaughter charges in Floyd's death, showing how his alleged attempt to pass a phoney $20 bill at a neighbourhood market last May escalated into tragedy one video-documented step at a time.

A security-camera scene of people joking around inside the store soon gave way to the sight of officers pulling Floyd, who was Black, from his SUV at gunpoint. The extended body-camera footage gave jurors the fullest view yet of the roughly 20 minutes between when police first approached Floyd's vehicle to when he was loaded into an ambulance.

When Floyd was finally taken away by paramedics, Charles McMillian, a 61-year-old bystander who recognized Chauvin from the neighbourhood, told the officer he didn't respect what Chauvin had done.

“That's one person's opinion,” Chauvin could be heard responding. “We gotta control this guy 'cause he's a sizable guy... and it looks like he's probably on something.”

Floyd was 6-foot-4 and 223 pounds, according to the autopsy, which also found fentanyl and methamphetamine in his system. Chauvin's lawyer said the officer is 5-foot-9 and 140 pounds.

Chauvin, 45, who is white, is charged with murder and manslaughter, accused of killing the 46-year-old Floyd by kneeling on Floyd's neck for 9 minutes, 29 seconds, as he lay face-down in handcuffs. The most serious charge against the now-fired officer carries up to 40 years in prison.

Floyd's death, along with the harrowing bystander video of him gasping for breath as onlookers yelled at Chauvin to get off him, triggered sometimes violent protests around the world and a reckoning over racism and police brutality across the U.S.

As Floyd was pinned down by Chauvin and other officers, McMillian, the bystander, could be heard on video saying to Floyd, “You can't win” and “Get up and get in the car.”

Floyd replied: “I can't.”

The defence has argued that Chauvin did what he was trained to do and that Floyd's death was not caused by the officer's knee, as prosecutors contend, but by Floyd's illegal drug use, heart disease, high blood pressure and the adrenaline flowing through his body.

Events spun out of control earlier that day soon after Floyd allegedly handed a cashier at Cup Foods, 19-year-old Christopher Martin, a counterfeit bill for a pack of cigarettes.

Martin testified Wednesday that he watched Floyd's arrest outside with “disbelief -- and guilt.”

“If I would've just not tooken the bill, this could've been avoided,” Martin lamented, joining the burgeoning list of witnesses who expressed a sense of helplessness and lingering guilt over Floyd's death.

Martin said he immediately believed the $20 bill was fake. But he said he accepted it, despite believing the amount would be taken out of his paycheque by his employer, because he didn't think Floyd knew it was counterfeit and “I thought I'd be doing him a favour.”

Martin then second-guessed his decision and told a manager, who sent Martin outside to ask Floyd to return to the store. But Floyd and a passenger in his SUV twice refused to go back into the store to resolve the issue, and the manager had a co-worker call police, Martin testified.

Martin said that when Floyd was inside the store buying cigarettes, he spoke so slowly “it would appear that he was high.” But he described Floyd as friendly and talkative.