Curtis Calvin Pixley Jr. was only 16 but he already had a reputation as a neighborhood terror, someone with a penchant for stealing cars and starting fights in Northeast Washington.

Then, last fall, he got a gun. And during the next three weeks, according to prosecutors, he killed one person and wounded four others in a series of robberies in which he shot his victims even after they emptied their wallets.

"The violence was completely gratuitous," said Assistant U.S. Attorney Kenneth C. Kohl. "He chose the most innocent and vulnerable victims."

Pixley, of the 2900 block of South Dakota Avenue NE, pleaded guilty Monday in D.C. Superior Court to first-degree murder while armed and two counts of assault with intent to kill.

In his videotaped statement to police, played during the court proceeding, Pixley repeatedly referred to his murder victim, Patricia Ann Davis, in a derogatory way.

Davis, 37, was slain Nov. 22 when Pixley and two teenage accomplices burst into her home in the 3000 block of Adams Street NE as she was preparing her family's Thanksgiving turkey. The intruders wanted money. When Davis said she had no cash, Pixley shot her twice in the face, prosecutors said. Then, as she tried to flee, he shot her in the back.

Prosecutors said Davis's death capped a three-week crime rampage that began when Pixley got a revolver. They said they don't know how he got the gun, but they know what he did with it.

"He unleashed a wave of violence against total strangers," Kohl said.

Besides the Davis killing, Kohl said, police believe that Pixley carried out at least three carjackings and three robberies. He said Pixley shot one woman in the back during a robbery, shot another woman in the head as her 8-year-old son watched in horror, and shot two men as they tried to run from him.

All of the crimes occurred in November within blocks of Pixley's grandmother's home, where he lived.

Pixley pleaded guilty to shooting Lorraine Stanford, 41, the mother of the 8-year-old, in front of her home at 24th and Otis streets NE. Prosecutors said he accosted Stanford on Nov. 6, as she and her child got out of their car, and demanded money. She gave up her purse, but Pixley still shot her in the back of the head.

He also pleaded guilty to opening fire Nov. 8 on three men who had gathered at 22nd and Taylor streets NE, prosecutors said. The gunfire hit John House, 58, in the chest and back, and hit James Vessells, 68, in the leg. A third man, Robert Vessells, 61, was not wounded. Prosecutors said the three men were at the corner exchanging vegetables that one had brought from a farm.

Pixley has been jailed since his arrest a few days after Davis was slain. He could face a life prison term when he is sentenced Oct. 22 by Judge Reggie B. Walton.

The others accused of killing Davis, Terrence Wynn, 17, and Chancelin Matthews, 19, also of Northeast Washington, have pleaded guilty to second-degree murder.