A judge set bail of 1 million U.S. dollar on Thursday for three former Minneapolis police officers charged with aiding and abetting in the murder of George Floyd, a black man whose killing while in police custody set off widespread protests.

Bail for the three defendants, who made their first court appearance on Thursday, would be lowered to 750,000 U.S. dollars if they agreed to certain conditions, including forfeiting any personal firearms. Judge Paul Scoggin set each man's next court appearance for June 29.

Thomas Lane, J. Alexander Kueng and Tou Thao were charged on Wednesday with aiding and abetting second-degree murder and aiding and abetting second-degree manslaughter. They face up to 40 years in prison if convicted.

Derek Chauvin, the police officer who pinned his knee onto Floyd's neck for nearly nine minutes and charged with second-degree murder, is due in court on Monday. 

All four officers have been fired from the Minneapolis police department. None of the three men who appeared in court spoke.

Dressed in orange jumpsuits, they appeared separately in back-to-back hearings lasting about five minutes each. In Minnesota, pleas are not entered in preliminary hearings.

"What was my client supposed to do but to follow his training officer's orders?" Lane's attorney, Earl Gray, said as he argued against the bail amount. "He was doing everything he thought he was supposed to do." 

In the May 25 killing, Lane and Kueng were filmed helping keep Floyd pinned to the ground by putting their weight onto his back and knees. Thao stood watch between onlookers and the officers who were holding Floyd down.

A memorial for Floyd was also held Thursday in Minneapolis, which saw the attendance of his brother Philonise.

Speaking at the memorial service held at a chapel in Minneapolis' North Central University, Philonise recalled moments he shared with Floyd earlier in their lives.  

"It's crazy man, all these people came to see my brother, it's amazing he touched so many hearts," he said.

Floyd family lawyer Ben Crump also said during memorial service that the police's action that day was "evil."

Thursday's mourners in the city also included Minnesota Governor Tim Walz and Minneapolis Mayor Jacob Frey. The latter was also pictured breaking down in tears, his body heaving, as he knelt with one hand on Floyd's casket.

Meanwhile some 5,000 people gathered in New York Thursday afternoon for a memorial service joined by Floyd's brother, Terrence, in Brooklyn's Cadman Plaza. 

He said he is proud of the protests but not the destruction, referring to the violence and looting that had emerged in demonstrations.

"My brother wasn't about that," he added.

Local officials, including New York City Mayor Bill de Blasio and New York State Attorney General Letitia James, also joined the vigil.

"George Floyd cannot have been allowed to die in vain," the mayor said. "We will make a peaceful change. To the Floyd family, we stand with you. Black lives matter in this city. Black lives matter in America."

Terrence then led the protesters on a march across the Brooklyn Bridge to Manhattan's Foley Square under the scorching sun.

(With input from agencies)