What’s Behind the Murder Spike in Brooklyn?

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For years, city officials have worked to promote New York as the safest large city in America. Its transformation from urban war zone in the early 1990s to shining metropolitan destination has long been a point of pride for the Police Department. For two decades, murder rates have continued to plummet.

But in the first three months of this year, that trend took a concerning turn in the opposite direction, driven by a steep spike in murders in Brooklyn. As of March 24, the borough had recorded 28 homicides so far this year, compared with 17 in the same period last year, a 64 percent increase.

During the same period, police officials said the number of murders in the rest of the city fell slightly, from 43 to 41. Murders went up in significantly in Manhattan, but fell in the Bronx, Queens and Staten Island.

Crime rates rise and fall periodically and it is too early to tell if the increase in killings foretells a new crime wave that would challenge the sense of security that has become part of the city’s identity. Over time the increase may be offset by quieter periods, and trends that appear worrisome in March often level off by August.

“There are month to month fluctuations, not necessarily indicative of a trend,” said Chief Lori Pollack, who oversees crime control strategies.

Still, the spike in murders in Brooklyn — particularly in the 10 precincts in the Brooklyn North command — has left police officials scrambling to contain it. Senior commanders said a small number of people linked to street gangs appear to be responsible for the recent wave of shootings.

“They’re gang-related shootings, and it’s the same related individuals who are showing up,” said Chief Terence A. Monahan, the department’s highest-ranking uniformed officer. He added that some of the people detained in connection with recent shootings were facing gun charges in other boroughs and had been released on bail.

There have been 21 killings so far in the Brooklyn North precincts, compared to 12 at this time last year. Many of those killings have been clustered in neighborhoods like East New York and Brownsville. Others have occurred on the edges of rapidly gentrifying areas like Bushwick and Bedford-Stuyvesant, where there were four murders within a five-block radius earlier this year.

To counter the violence, the police commissioner, James P. O’Neill, announced in March that the department would add officers to four of the city’s problem precincts, including the 79th Precinct, which covers parts of Bedford-Stuyvesant and south Williamsburg. The department is also shifting officers from Queens into public housing complexes in northern Brooklyn, where much of the violence has flared.

The addition of officers has already led to a significant increase in gun arrests in Brooklyn, the police said.

“This is how we’ve reduced crime, by focusing our resources,” Mr. O’Neill said. “I think we’ve turned a corner in Kings County. We understand what the mission is, and that’s to keep people safe.”

The violence in Brooklyn is still a far cry from the crest of the murder wave of the early 1990s. By April in 1993, for instance, the same 10 precincts in Brooklyn North already had more than 80 killings.

Still, the memory of the days when the city was known as one of America’s most dangerous places haunts the police and elected officials. Mayor Bill de Blasio said the police department was employing a number of strategies to counter the violence, including programs to forge tighter bonds with the community in high-crime precincts.

“We’re not going to stop until we make more fundamental changes, and make people safer and make sure they feel safer at the same time,” Mr. de Blasio said.

Many residents and business owners in Bedford-Stuyvesant and Clinton Hill said they were aware of recent shootings, yet do not feel as if their communities are under siege.

Denise Davis, 52, said a shooting in January inside the Lafayette Gardens public housing complex stood out in her mind because the neighborhood had become safer in recent years.

“There used to be a lot of shooting over here — especially right here,” Ms. Davis said as she stood near the intersection of Franklin and Lafayette Avenues. “It has quieted down a little bit, but you’ve still got robberies going on.”

There were some signs of insecurity and unease. “Drugs, guns and noise,” was the neighborhood portrait offered by one man as he walked along Franklin Avenue. He declined to give his name.

“Things have gotten shadier lately,” said Hannah Weikert, a senior at Pratt Institute who shares an apartment in Clinton Hill.

In Bedford-Stuyvesant, Henry Miller, 51, a retired sanitation worker who runs a volunteer program to help steer neighborhood students toward college, said that few weeks ago a man climbing into an Uber car was fatally shot just outside his window on Bedford Avenue, near Greene Avenue.

But Mr. Miller said he took a long view, having lived in the neighborhood since childhood, and through a period of drug-fueled violence in the 1980s and 1990s.

“You’re not scared at night any more walking home,” he said. “Although I say to friends of mine, ‘This is still Bedford-Stuyvesant.’”