A 14-year-old was charged yesterday in the killing of a teenager last week near the Georgia Avenue-Petworth Metro station in Northwest Washington, police said.

Detectives are seeking a second unidentified suspect in the slaying of David McMorris, 16, who was shot about 9:30 p.m. July 21 while with a group of men in the 3700 block of Georgia Avenue NW.

Three people were wounded, including two who are paralyzed, police said.

Police officials said that it is unusual for a suspect so young to be charged with first-degree murder, adding that they did not have any evidence of violence in the teenager's past.

They credited a witness with providing information that helped lead to the suspect, whose name was not released because of his age.

The break in the case came after police returned to the shooting scene Thursday night and set up a checkpoint in hopes of turning up new leads. They said the witness approached officers about 10:30 that night and reported spotting one of the gunmen on a bicycle nearby. Officers then stopped the 14-year-old and took him into custody, police said.

The earliest age at which juveniles can be tried as adults in the District is 15, compared with 14 in most states, including Maryland and Virginia. Under D.C. law, the longest a 14-year-old could be confined is until age 21.

The suspect made his first appearance yesterday in D.C. Superior Court. Although juvenile proceedings typically are closed, The Washington Post attended the hearing on the condition that the 14-year-old not be identified.

Detective Elbert Griffin testified that the shooting took place after a fight or argument less than an hour earlier on nearby New Hampshire Avenue NW. The 14-year-old and another assailant allegedly approached McMorris's group and opened fire. One victim was shot in the initial burst of gunfire, and the two gunmen then ran across Georgia Avenue, firing indiscriminately, striking the others, the detective said.

Before the shooting, the 14-year-old apparently had argued with one of the four victims, a man who was paralyzed from the neck down from his wounds, Griffin said. Another man was shot in the back and is partly paralyzed, but his paralysis might not be permanent, Griffin testified.

Griffin told the court that the 14-year-old contends that he was in a barbershop at the time of the shooting.

The arrest comes as police and other District officials battle a spike in the killings of juveniles.

"It's a sad indictment of a generation when you have a 14-year-old killing a 16-year-old," said Cmdr. Hilton Burton of the 4th District, whose officers arrested the teenager Thursday night. "That's a scary situation."

Just an hour before the witness came forward, Burton and other police officials had attended a community meeting in the Petworth neighborhood, where residents had complained about teenagers loitering and causing trouble.

D.C. Council member Adrian M. Fenty (D-Ward 4) said that neighborhood residents were relieved a suspect had been arrested but that they remained concerned about drug dealing in the area.

The shooting took the life of a 16-year-old who had moved to Washington recently after difficulties at home in Lancaster, Pa., relatives said. McMorris, known for his love of video games and skateboarding, had gotten into a fight with his mother in December and was sent briefly to a group home, relatives said last week.

After seeking help from other relatives, he moved to the District to live with his aunt, Bette McFadden, the relatives said. His grandfather also lives in the city.

McMorris attended Theodore Roosevelt Senior High School, family members said. He was having a difficult time with his studies and often just wanted to play outside, family members said.

The relatives said they tried to counsel the teenager about avoiding the dangers of violence.

Before he was shot, McMorris told his aunt he wanted to hang out with neighborhood buddies on Georgia Avenue. "I can't stay cooped up in the house," his aunt recalled him saying before he left. "He said, 'I can't live in fear. You can't live in fear.' "

Staff writer Nicole Fuller contributed to this report.