A series of unusual violent crimes in Cambridge over the past weeks has left community leaders concerned for residents’ safety, with some calling for an increased police presence in their neighborhoods.

A fatal street stabbing in the last days of May, three shootings in five days early in June followed by a reported double rape at the end of the month constitute a surprising rise in violent crime in a city that averaged two murders per year over the course of the last decade.

Cambridge Police Department spokesperson Frank Pasquarello discounted suggestions that the city was experiencing a crime wave.

“Cambridge is a very safe place to live and work. It’s just unfortunate that we’ve had three shootings within five or six days,” he said.

None of the victims of the recent shootings were randomly targeted, Pasquarello noted.

“It’s believed that these were not random acts of violence...in every case, the suspects knew the person they were shooting at.”

But in Riverside, the neighborhood where recent violence has been concentrated, some residents are convinced that the crimes reflect larger trends of rising violence and reveal a need for heavier law enforcement.

“I think it’s disgraceful. It’s a very sad time for us,” said Riverside resident Joan Qualls-Harris. “I think this sort of thing is happening across the country, and I’m afraid that it’s something that’s not going to stop if we don’t have police and community connected to address the issue.”

Residents say a decrease in the number of officers—due to retirements, according to city officials—is leaving neighborhoods under-policed.

Harris said she thinks that the key to mitigating crime rests with the police’s expertise.

“I think we need more and very serious police protection in the community, because I think these kinds of activities are happening among people the police are familiar with,” she said.

Members of the community scheduled two meetings last month to address the recent surge of crime, according to Riverside resident Alec Wysoker ’84.

Though no decision on an appropriate response has yet been reached, Wysoker said, several residents issued a call for more community policing.

According to Mayor Michael A. Sullivan, his office has been working closely with the police commissioner to enhance law enforcement resources. The Cambridge Police Department recently sent a group of newly hired recruits to the state police academy and expects them to join the force by the end of the summer.

The city is also reevaluating its approach to policing, Sullivan said. Currently, a pilot program aimed at establishing an effective community-based policing system is underway in the Area 4 neighborhood, which abuts the Riverside district.

“We are continuing to look at what community policing should be,” Sullivan said. He said he hopes the pilot program will be able to expand throughout the city.

“We want residents to recognize the lieutenant who oversees their neighborhood,” he said. “We want them to know their beat officers.”

But Sullivan echoed Pasquarello in saying that residents shouldn’t read too deeply into the recent series of crimes. “The fear of crime may outpace the reality, and that can be paralyzing to a community,” he said.

Blood on the Streets

An alleged killer remains in custody in Florida where he fled, another man is dead and five victims are recovering from injuries sustained over the last month and a half in what Pasquarello described as apparently unrelated incidents.

On May 30, an East Boston resident was stabbed outside Pizzeria Uno on JFK Street. James Winquist, 19, of Hingham is being held for lack of bail in connection with the crime. The unidentified victim, described by witnesses as an African-American male, was taken to Beth Israel hospital where he underwent emergency abdominal surgery, but was later released.

Robert Florio and Sarah Butler were also arraigned in connection with the crime, according to Emily LaGrassa, a spokesperson for the Middlesex District Attorney’s office.

Five days later, 37-year-old Daryn Dupree of Cambridge was allegedly shot several times in the legs and lower torso by Jose Dejesus, 31, of Cambridge, at the intersection of River Street and Putnam Avenue. Jose Fontanez, 29, also a Cambridge resident, was arrested and charged in connection with the shooting as well.

Pasquarello said it appeared the shooting was not random, and that Dupree was personally targeted in the attack.

According to police, another shooting followed on June 6, when a male assailant approached an unidentified man seated in a parked car by the intersection of Putnam Avenue and Magee Street and fired several shots into the vehicle before fleeing. Police have not recovered a weapon or issued any warrants in connection with the shooting. Pasquarello said the motive behind this incident is still unknown but that investigators think it was also a targeted act. The victim survived and has been released from the hospital.

In the third shooting in under a week, Robert Scott, 26, of Cambridge, was gunned down in broad daylight on the afternoon of June 8, while he waited at a bus stop on the corner of Mass. Ave. and Walden Street. According to police, Scott, the father of a five-year-old girl, was standing in front of the KFC and Taco Bell located near Porter Square when he was approached by a male assailant who allegedly produced a handgun and opened fire. Scott suffered four fatal shots to the torso.

In a statement dated June 18, Middlesex District Attorney Martha Coakley identified Scott’s alleged killer as Markendy Jean, 25, of Malden. Jean, who fled to Florida following the crime, surrendered himself to authorities last week, according to LaGrassa. He is scheduled to return to Massachusetts in custody within the next two weeks, LaGrassa said.

Pasquarello declined to comment on a possible motive or whether this incident was related to either of the previous two. But the Cambridge Chronicle reported last week that Jean was fired earlier this spring for fighting with Dupree, the victim of the first shooting.

The Chronicle also reported that a search of court records revealed Jean has a lengthy criminal record—including convictions for unarmed robbery, drug charges and assault and battery on a police officer.

On June 22, an unidentified Billerica girl told the Medford police she had been sexually assaulted over the weekend. She and a companion, 12 and 14 years old respectively, were allegedly raped at a party in Cambridge, the Chronicle reported. The two girls have since been released from medical care. LaGrassa declined to discuss the details of the case, which is still being investigated. But she said that the actual location of the rapes is not yet clear.

“The Medford, Cambridge and Somerville police are all working together,” she said. Officers at the three agencies declined to comment on the case in progress.

LaGrassa yesterday said investigators were not prepared to name any suspects.

There Goes the Neighborhood

While Harris said the recent crimes point to the need for a stronger police presence, others said the violence might be indicative of deeper weaknesses in the fabric of social support.

“I don’t think this rash of violence is anything insidious, I think it’s a result of the way young people are taking out their disagreements with one another,” said City Councillor E. Denise Simmons.

Wysoker said he thought that recent crime in Cambridge ultimately resulted from entrenched social influences.

“I believe that the root causes of this kind of crime are historical and institutional injustices that permeate the society,” he said, citing economic inequity within the community. “And until we solve those problems the crime will continue.”

Simmons said there are insufficient programs in Cambridge that serve struggling residents between the ages of 18 and 30.

“If we have programs, they certainly are not prolific enough,” she said. “What we have found is that this age group is too old for most of the programs we provide...Until we reach that group, we’re going to continue to have a problem.”

While Simmons did not have any recommendations for specific programs that might remedy this situation, she said a solution in sight.

“Very little of what we need needs to be invented,” she said. “It probably exists somewhere.”

Sullivan said one such initiative is already underway.

“We are increasing the number of city jobs available for youth. We are going to be in excess of 700 this year,” he said—an increase of over 50 summer jobs from last year, he added. “We’ve also contracted with a group to work with those aged 20 to 30. We have great resources here and we continue to reach out.”

—Ankur A. Patel contributed to the reporting of this story.

—Staff writer Nathan J. Heller can be reached at heller@fas.harvard.edu.

—Staff writer Andrew M. Sadowski can be reached at sadowski@fas.harvard.edu.