There is a story about Demetrius Emmanuel Thompson that is family lore: When he was 12, he returned from a 7-Eleven accompanied by a police officer who said Demetrius and a friend were trying to break into a car with a coat hanger.

Talaya Thompson told the officer to take him to jail. The officer drove Thompson around the block enough times to make him think he was getting locked up, then took the quivering and contrite boy home.

“I promise I won’t do anything like that again, Ma,” he said, Talaya Thompson recalled Thursday.

Thompson kept his word. His mother didn’t have to speak to a police officer about her son again until Thursday morning, when two D.C. detectives found her on her graveyard shift as a certified nursing assistant and told her that her son had been fatally shot while riding a Metrobus.

Police said that Thompson, 22, was found in the street in the 2100 block of Alabama Avenue SE shortly after midnight. He had been aboard a W4 bus heading east on Alabama Avenue SE, toward his mother’s home.

D.C. police released a short video Thursday showing what they described as two “persons of interest” boarding the bus just before the shooting and asked for the public’s help in identifying the people in the clip.

Thompson’s death continues a string of violence in the District. Five people were killed between Saturday and Monday. There was a pause, and then Thompson’s death on Thursday.

The news shocked Thompson’s family as they gathered in Talaya Thompson’s Fairfax Village home Thursday to recall the soft-spoken son, nephew and brother they called “D,” known for his megawatt smile. Talaya Thompson was so determined to keep violence away from her children that she didn’t allow them to have even toy water guns.

Relatives were concerned about what people might think when they heard of Thompson’s death.

“Most people, when they hear that a young black man in Southeast was killed, they assume he was selling drugs or something bad — but not Demetrius,” said Talaya Thompson. “I just know this was a senseless murder. It has to be over something silly, because he’s not one of those people.”

In November 2009, George Rawlings was shot and killed in Northeast Washington as he boarded an X2 Metrobus after leaving a childhood friend’s funeral. Metro spokesman Dan Stessel said Thursday that had been the most recent fatal shooting aboard a bus and that homicides on a Metrobus are “extremely rare.”

“Crime on Metro is trending downward as a result of joint policing strategies with MPD and other jurisdictional law enforcement agencies,” Stessel said. The most recent homicide at a rail station was in May 2010, he said.

Demetrius Thompson holds his daughter Nseya, then three months old, in 2009. (FAMILY PHOTO)

Aboard the W4 on Thursday, some passengers talked about the shooting, while others knew nothing about it. College student Alex Lyles, 20, was headed to a church near the site of the shooting as the bus moved along Alabama Avenue, past the tidy Henson Ridge development of new townhomes and a retail shopping center.

“It’s a cause of concern,” Lyles said. “I don’t ride the bus at midnight, but still, it’s enough to cause me to raise an eyebrow.”

Demetrius Thompson had two children. His mother had talked to him about going to college, but she said he was was focused on finding a job and providing for his family. He got his commercial driver’s license in August after studying for weeks and taking practice tests. He came home and flashed the license, and his mother sent text messages to friends and family.

When the detectives appeared this week, Talaya Thompson thought, “ ‘What in the world did ‘D’ do?’’ I had no idea.”

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Staff writer Dana Hedgpeth contributed to this report.