District and Montgomery County police are investigating a rash of robberies in the Chevy Chase area to see if they are related to the killing Saturday night of a 63-year-old lawyer, authorities said yesterday.

D.C. police said they have no suspects in the slaying of John Winston, who was shot outside his Chevy Chase Circle town house, possibly during a robbery attempt.

Meanwhile, three more people were killed in the District yesterday, bringing the city's homicide toll for the year to 383. One of of the victims was a 27-year-old man who was shot during a robbery as he walked home from work in Northwest Washington shortly after midnight.

Montgomery police detective Jack Toomey said county police have investigated two robberies near Chevy Chase Circle this month.

In one, a 63-year-old woman was robbed at knifepoint Oct. 7 after leaving morning services at Blessed Sacrament Catholic Church, Toomey said. She was accosted by a man hiding in the bushes about a block from the church, he said.

The most recent robbery occurred in the county's Chevy Chase Village area Oct. 14, when a middle-aged woman was robbed by a man with a handgun as she was leaving her car to pick up her daughter from a party, Toomey said.

Another robbery occurred nearby in the District that evening, which was a source of concern to residents, said Patricia Baptiste, chairman of the Chevy Chase Village Board of Managers.

Baptiste said it is a problem for authorities tracing crimes in the county and city because criminals cross back and forth.

In yesterday's violence, Carl Anthony Green, 27, was shot to death at 11th and Lamont streets NW shortly after midnight as he and a friend walked home from work. Police said the two were confronted by at least two men who demanded money and shot Green in the head.

The bloodshed continued last night. Shortly before 9:30, a man was found slumped in the driver's seat of a Buick Skylark behind an apartment building in the 1200 block of Valley Avenue SE. He had been shot in the head, and detectives said it was not immediately clear how long he had been dead.

About the same time, another man was found dead in the unit block of M Street SE, police said. The man, who was on the sidewalk near a liquor store, had been stabbed several times in the abdomen.

Neither man was identified, and no other details of the killings were available.

In still another incident, a 21-year-old man was in serious condition last night at Washington Hospital Center after being shot in the head in what police believe was a random shooting.

Officers said the man, whose name was not released, was wounded about 8 p.m. as he sat in front of an apartment building in the 400 block of Edgewood Street NE. More than 15 shell casings were found in the area, police said.

Four other people were killed in shootings over the weekend.

In addition, an Oct. 7 death was classified yesterday as a homicide. It originally had been considered a suicide.

Eric Lajuan Mason, 18, was found lying in the 2700 block of Martin Luther King Jr. Avenue SE with a gunshot wound in the head. After a preliminary investigation, police determined the wound was self-inflicted and that it occurred during a struggle.

In response to the recent surge in violence, D.C. police began last night to use a special "rapid deployment unit" of about 100 officers to target high-crime areas.

Staff writer Stephen Buckley contributed to this report.