The bike was orange and had been a gift from a father to his son on the son’s 10th birthday. After a tire went flat, the bike sat for months in the basement of the Northeast Washington home where the boy lives with his mother.

The father, who lives apart from his son, recently had the flat repaired, and on Sunday, he returned it to the boy, now 12 and a student in middle school.

On Monday, D.C. police said, another boy shoved the 12-year-old away from the bicycle and stole it near the victim’s house in the Carver-Langston neighborhood.

The suspect is 9 years old, police said.

“My son ran after him but couldn’t catch him,” said the victim’s mother, 52, who called 911 when she heard her son crying outside at about 5:30 p.m.: “Mama, somebody stole my bike.”

Based on information from the victim, police broadcast a description of the suspect over Twitter. They wrote that there was a lookout for a “9 yoa, no shirt, blue basketball shorts, brown hair, orange bike.”

Although this was just one of 1,678 robberies reported in the District this year, the age of the suspect stood out. Descriptions from victims can often be wrong, but not in this case, police said.

[Police issue lookout for 9-year-old robbery suspect]

Police quickly found the young suspect, who was riding around the neighborhood on the bike. A police report says the youth was charged with robbery by force and violence and taken to authorities who handle juvenile cases.

The victim’s mother — who did not want to be identified to protect her son’s identity — said the boy’s father bought the Magna bike at Target for $100. After the flat, the mother put the bike away, she said, but the boy’s father learned of a place that would fix it free.

The 12-year-old took the bike for a ride Monday afternoon, going no farther than the edge of an alley near his home. The chain came off, and he was putting it back on, he later told police, when the other boy approached and asked if he could ride the bike. The owner said no.

Police said in a report that the victim “stated that [the 9-year-old] pushed him back, grabbed onto his bike and rode off traveling westbound on Lang Place NE.” The victim’s mother said her son, though older than the suspect, is small for his age, standing about 4 feet 5 inches.

She said she has worked to keep him safe. He is allowed to walk on his own no farther than the four blocks to school and a friend’s home at the other end of the block. She watches his friends closely and made sure he cut off ties with a youth she described as trouble.

Now, the mother said her son doesn’t want to go outside. “I’m going to have to take him to school,” she said. “It’s just sad what happened. This morning when I went to work, he was like, ‘Mommy, don’t leave me today.’ ”