MINNEAPOLIS (AP) — After the ambulance took George Floyd away, the Minneapolis officer who had pinned his knee on the Black man’s neck defended himself to a bystander by saying Floyd was “a sizable guy” and “probably on something,” according to police video played in court Wednesday.

The video was part of a mountain of footage — both official and amateur — and witness testimony at Officer Derek Chauvin’s murder trial that all together showed how Floyd’s alleged attempt to pass a phony $20 bill at a neighborhood 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 from his SUV at gunpoint, struggling to put him in a squad car as he frantically said he was claustrophobic, and then pinning him to the pavement.

When Floyd was finally taken away by paramedics, Charles McMillian, a 61-year-old bystander who recognized Chauvin from the neighborhood, 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. Chauvin’s lawyer said the officer is 5-foot-9 and 140 pounds.

Chauvin, 45, 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 white 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.

Events spun out of control that day soon after Floyd allegedly handed at 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 paycheck by his employer, because he didn’t think Floyd knew it was counterfeit and “I thought I’d be doing him a favor.”

Martin said he initially planned to just put the bill on his own “tab” but then second-guessed himself 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.

The defense 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.

After police arrived that day, Martin went outside as people were gathering on the curb and yelling at officers. He said he saw Officer Tou Thao push one of his co-workers. Martin said he also held back another man who was trying to defend himself after being pushed by Thao.

Another witness, who parked behind the SUV that Floyd was driving, said he saw two officers approach Floyd’s vehicle as one drew a gun, opened the driver’s door and pointed the weapon at Floyd.

Christopher Belfrey, 45, said he was “startled” and began taking video through his windshield. Prosecutors played some of that footage too.

Eventually, Chauvin and Thao arrived on the scene, and Floyd thanked officers as they pulled him out of the squad car and put him on the ground.

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

Floyd replied: “I can’t.”

McMillian testified that he had talked to Chauvin five days earlier, telling him that at the end of the day, everyone wants to go home to their families safe.

Wednesday morning’s testimony was briefly interrupted when a juror stood and raised her hand and gestured toward the door. She later told the judge that she had been feeling stress and having trouble sleeping, but told the judge she was OK to proceed.