Four women sitting in a car outside 36 Harlem St. were shot around 9:20 p.m. on Sunday. Two were pronounced dead at the scene, while the other two were taken to local hospitals - one with life-threatening injuries from which she died Monday - the Boston Police Department reports. The day before, a man was shot at 9 Page St., just on the other side of Glenway.

About 90 minutes after the quadruple shooting, a man was surrounded by a group of other men near Burke High School off Washington Street and shot in the leg.

At a press conference with Mayor Tom Menino Monday morning, Police Commissioner Ed Davis said police were looking for a white SUV with a black top and very bright lights in front.

Davis said an image of the SUV was snapped by a camera the city had installed nearby as part of a citywide program to install surveillance cameras in high-crime areas.

Davis said initial indications were that the shootings were not random, but he declined to detail any further aspects of the investigation, including any possible links to the Page Street shooting.

Family members and friends identified the three woman as: Sharrice Perkins, who was part of a state championship double-Dutch jump rope team in 2007; Kristen "Kae" Lartey, who had just graduated St. John's University in New York and was a writer; and Marie Phillip, who had a young daughter.

Menino and Davis said the areas around shooting scenes in Dorchester and Roslindale - where four men were shot Saturday, one fatally - will be flooded with extra police, street workers and city anti-violence experts, in part to try to gain additional evidence, but also to try to calm things down.

Menino said the city wants to "stop a cycle of violence" that often occurs in the aftermath of mass shootings like these. Davis said workers will attempt to calm neighbors and show them that, despite the violence, "we have a safe city here."

"Up until this weekend, we've had a relatively uneventful summer," Davis said.

The Harlem Street murders were just a few doors down from where sisters Stephanie and Judith Emile were shot to death last November.

Dorchester and Mattapan murders over the past year.