A 16-year-old knocked a woman off her bicycle along the Metropolitan Branch Trail on Monday evening and demanded her belongings, according to D.C. police. The victim reached into her purse and handed the teenager a single $1 bill.

The victim said it the only cash she had.

“He could have easily taken my credit cards, but he seemed happy with the dollar,” the 31-year-old woman said. “I told him if he wanted more, I could got to an ATM and get more cash. He said, ‘Yeah, do that.’”

The woman said she left on her bicycle and flagged down a passing police officer. Authorities said officers on mountain bikes quickly arrested the youth, near where the robbery had occurred. The victim said she thinks he was waiting for her to return from the bank machine. The youth was charged as a juvenile with robbery.

Monday’s attack came one week after police said a 14-year-old boy tried to sexually assault a woman along the trail on June 16, near the 1800 block of Fourth Street NE. That suspect was arrested and charged as a juvenile with robbery and assault with intent to commit first-degree sexual abuse.

Police said they do not think the attacks — which occurred blocks apart in Eckington — are related but are stepping up patrols along the popular trail used by exercisers and commuters alike. In June 2013, a bicyclist in his 30s was severely beaten by as many as 15 youths on the trail.

The victim from Monday’s robbery — which occurred about 5:15 p.m. near the 300 block of R Street NE — said she remembered last year’s assault and worried that more attackers by waiting for her.

She said she saw the youth standing in the middle of the trail as she approached.

“I thought it was a little sketchy,” the woman said. “As I rode past him, he turned and ran toward me and pushed me off. When I got up, he was coming toward me. I asked him what he wanted and he said ‘money.’”

The victim said she often commutes to work and home on the trail, but did not do on Tuesday.

Police mentioned the robbery on the department’s Internet bulletin board, where Lt. Gary Durand of the 5th District noted the “rapid response” of bicycle officers who made the arrest.

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