A District youth was fatally shot yesterday afternoon in a Northeast Washington alley, police said.

Jerome T. Marshall, 17, was shot once in the chest by someone riding in a dark-colored sport-utility vehicle, police said. He was pronounced dead about an hour later at Howard University Hospital.

The gunfire took place about 1:20 p.m. as Marshall walked through an alley at L Street and 17th Place NE, police said. After he was wounded, Marshall ran a short distance to the 1000 block of Bladensburg Road NE, where he collapsed in front of a store.

Police searched for the vehicle but made no arrests.

D.C. Police Chief Charles H. Ramsey expressed frustration with the rising homicide rate among juveniles when the overall number of killings in the city is on the decline. Marshall was the 23rd juvenile to be slain this year; last year, 12 juveniles were killed.

"It's always tragic when you have anyone killed. When you have juveniles, again, it's tragic," Ramsey said.

Alemseged Woldemichael, 27, owner of Rim's Market, where Marshall collapsed, said he heard several gunshots and went outside to see Marshall running from the alley. Woldemichael said Marshall was a daily customer, often buying bottled water and potato chips.

"This is not my idea of America," said Woldemichael, who came to the United States from Ethiopia. "To see something like this happen, it's unbelievable."

Although Marshall lived in the 7800 block of 12th Street NW, his mother said that he was raised in the neighborhood where the shooting occurred and that he frequently spent time there. Denise Marshall described her son as a smart, mature teenager who helped her as well as his four younger siblings.

She said he recently earned his general equivalency diploma and hoped to work as an electrician.

Staff researcher Bobbye Pratt contributed to this report.