A memorial was set up at the location in Alexandria where Julian Dawkins was shot and killed. (John McDonnell/THE WASHINGTON POST)

The two men argued, then parted ways. But one of them, an off-duty Arlington sheriff’s deputy, came back — this time with his gun, handcuffs and badge, prosecutors said Friday.

Deputy Craig Patterson shot Julian Dawkins, 22, in the chest, the prosecutors said. As the young man lay dying in an Alexandria yard early May 22, Patterson called 911 and said Dawkins had come at him with a knife.

But that couldn’t have been true, according to prosecutors. Dawkins, a driver for the “PBS NewsHour,” was carrying a knife, but it was folded and clipped in his pocket.

That account was offered by prosecutors as Patterson, 44, who was charged late Thursday with murder, made a first appearance Friday in Alexandria General District Court. It was the most detailed account yet of how Dawkins ended up dead at the hands of a veteran law enforcement officer.

Still, many questions remain about the case, which has tested the patience of Dawkins’s relatives and friends. Prosecutors and police have refused to say how the two men first encountered each other, what they argued about or what occurred immediately before the shooting.

The hearing came on a day when friends and relatives gathered at Antioch Church of Christ in Alexandria to pay tribute to the young man whose life was cut short. Dawkins was a graduate of Alexandria’s T.C. Williams High School, where he played basketball, and he hoped one day to start a car-detailing business.

“To the family: You should know that — just like you — his ‘NewsHour’ family will not rest until we get the answers to the questions we all still have,” Gwen Ifill, a “NewsHour” senior correspondent, said at the funeral, according to a transcript. “And even when we do, we will continue to grieve with you, pray for you, and consider you our family, too. He was our balm and our rock.”

Patterson was arrested Thursday night at a home in Spotsylvania County, and he was charged with first-degree murder and using a handgun while committing a felony.

His newly appointed attorney, Joe King, declined to comment Friday. No one answered the door at a home where officials said Patterson lived in Alexandria, and no one responded to a written message left there. A woman connected to a Fredericksburg address listed for him in court records declined to comment.

In court Friday, Commonwealth’s Attorney S. Randolph Sengel told the judge that witnesses spotted Patterson and Dawkins arguing in the early morning of May 22 in the 100 block of Lynhaven Drive and heard Patterson yell that he would “be back” as he headed toward his home nearby.

Sengel said the witnesses told investigators that they then saw Patterson walk back to Lynhaven Drive, carrying his gun, badge and handcuffs.

Sengel said after Patterson shot Dawkins, he called 911 to say Dawkins had “pulled a knife.” That part of Patterson’s account, though, could not have been true, because the knife was in Dawkins’s pants pocket when police found him, Sengel said.

Before the confrontation with Patterson, Dawkins had been at a a celebration for a cousin who had just made the roster of the Washington Mystics basketball team.

Patterson appeared in court via a video monitor, wearing a black T-shirt and sitting next to public defender Melinda Douglas at a long table. He told Judge Becky Moore that he was unsure of his employment status with the Arlington Sheriff’s Office. The last he knew, he said, he had been placed on administrative leave.

The Sheriff’s Office on Friday said Patterson was placed on unpaid administrative leave after the charges were filed.

Moore appointed King to serve as Patterson’s attorney and ordered Patterson held without bond. She scheduled his next court date for June 7, giving Sengel and King time to arrange a preliminary hearing. Douglas had argued that bond should be set for Patterson, noting that he had cooperated with investigators and had not fled during the police investigation.

Dawkins’s relatives and friends have been pushing for officials to act. This week, about two dozen people gathered in front of the Alexandria courthouse to demand that authorities bring charges.

After the arraignment, Sengel and Alexandria Police Chief Earl L. Cook defended authorities’ decision not to charge Patterson immediately. Sengel said that the delay was based on prosecutors and detectives’ “continuing review of the evidence.” He said new information emerged as recently as Thursday.

Cook said that detectives could not ignore that Patterson worked in law enforcement but that it did not affect the investigation. “We have to do the right things to get to the point where we are today,” he said.

Alexandria Undersheriff Tony Davis said officials intended to keep Patterson jailed in Alexandria. Patterson would probably be held in his own cell, Davis said, and sheriff’s officials would “take necessary steps to keep him safe,” given his law enforcement work.

Dawkins’s mother, Gwen Pratt Miller, said she Friday that did not want to comment on the charges.

“I just buried my son,” she said.

Jennifer Jenkins contributed to this report.