Early Tuesday morning, 45 New Haven police officers and detectives raided dozens of locations across the predominantly black Dixwell and Newhallville neighborhoods. The operation was carefully planned: In the preceding days, New Haven police detectives met with agents from the Federal Bureau of Investigation to identify as many targets as possible.

The officers were determined to find the criminals who have murdered at least seven city residents since October — many of them execution-style, with a gunshot to the front or back of the head. The most recent murder occurred Jan. 3, when a 57 year-old man was found lying on a Newhallville street, shot in the head. He died later that day at a local hospital.

While crime throughout the city dropped 11 percent from 2008 to 2009, gun violence in the city’s black neighborhoods, such as Dixwell and Newhallville, did not. Of the 13 homicide victims in New Haven last year, 11 were black males killed by guns.

Leaders in New Haven’s predominantly black communities say seven of the eight murders in the last three months — all but the man stabbed outside Synergy nightclub on Crown Street in November — reflect a systemic problem with gun violence in the city’s neighborhoods.

Two community leaders said at a Board of Police Commissioners meeting Tuesday night that the murders have coincided with the releases of ex-felons from prison.

“We have felons leaving prison every week, and it appears in these recent cases, retaliation was the cause [of the murders],” Ward 22 Alderman Greg Morehead, who represents the Dixwell neighborhood, said. NHPD spokesman Joseph Avery said 25 ex-felons are released back into the city each week with little support for their reintegration.

“These black men are on a rampage,” black community leader and board member Bishop Theodore Brooks said at the Board of Police Commissioners meeting. “It’s put the police department and the city in a quandary. Everyone [in the community] knows what’s going on — head shots to the back, head shots to the front — but they are afraid to come forward and speak.”

Brooks wanted to know what the police are doing to stop the street warfare, and his comments struck a chord with Evelise Ribeiro, a board member whose relative was shot and killed last year.

New Haven Police Chief James Lewis said police are working on solving the problem and cited Tuesday’s raids as the largest part of the city’s aggressive strategy to stop the violence. The strategy involves identifying outstanding arrest warrants in violence-prone areas and using those warrants to search the areas for weapons and suspects.

Lewis said police have suspects or informants in all the seven recent murders and that the investigations are progressing, though more slowly than police would like. Lewis said he could not divulge the results of the searches or the details of other measures the police have taken because the investigations are ongoing.

The NHPD is also increasing traffic enforcement in the city’s high-crime areas in an effort to find illegal firearms and remove them from the streets, Lewis said. The hope is that by targeting all known criminal activity in the designated areas, police will find the murders’ perpetrators or obtain tips that lead to their arrests, Lewis added.

Meanwhile, as city law enforcement officials scramble to identify the murderers, city residents and community leaders are demanding aggressive action.

Local anti-violence organization the Brotherhood Leadership Summit, for example, met this month with Mayor John Destefano Jr. to discuss what more the city can do.

In December, more than 150 people attended a Board of Aldermen hearing the Brotherhood Leadership Summit helped to organize on violence in the black community. Speakers, including former New Haven Mayor John Daniels, blamed the increased gun violence on a variety of factors, including poverty, absent fathers and a lack of action on the part of government and the community.

Community activist Barbara Fair of People Against Injustice, a New Haven-based criminal-justice reform agency, said in a phone interview that the urban environment of poverty and helplessness in New Haven has been the cause of the violence.

“The environment that kids in these communities live in is one of despair, where there are no jobs and guns are as easy to buy as candy,” she said.

Police currently run several after-school programs to keep children off the streets and away from crime, funded by drug money that police seize, Lewis said. The city’s prison reentry initiative is funded by federal money, and recently, the federal government denied the city’s application for additional funds that would expand the program, said Amy Meek LAW ’09, the prison reentry program’s director.

If the violence continues at its present rate since October of about two murders per month, the city’s number of homicides will rise sharply after a 48 percent decrease last year. Since Lewis took his post in 2008, the department has implemented a more aggressive strategy for reducing crime known as “targeted activity policing.” The strategy involves officers making more traffic stops and arrests, and initiating more gun, drug and prostitution investigations. Police officials said the strategy was responsible for decreasing crime in New Haven.

“It takes clergy, families, businesses, all aspects of the community to truly rid all of our neighborhoods of violent activity,” said City spokeswoman Jessica Mayorga.

After 18 months at the head of the NHPD, Lewis will step down at the end of January.