A fatal double shooting on a block in East Harlem is highlighting the neighborhood’s uncertain future.

Across the street from the housing projects where the shooting took place stands a new “green” building of luxury condominiums, the Observatory, which has been touted as an environmentally-sensitive addition to the “up-and-coming neighborhood.” Its architects are advertising outdoor balconies with views of the city.

But at the East River Houses, where police said two men, Manuel Sabatera, 27, and Joshua Agard, 17, were shot in a playground on Wednesday night, some residents say they are often too afraid even to open their windows or go outside.

Standing next to yellow crime scene tape the morning after the shooting, residents recalled the last fatal shooting at East River Houses, in September. Then, police shot down an alleged drug dealer in the basketball courts. And in December there was a fatal stabbing.

“It’s a really bad neighborhood,” a resident of the East River Houses and acquaintance of Messrs. Agard and Sabatera, Gessel Urena, 18, said. “There’s drug dealing, there’s gang banging, and it’s getting worse.”

That is not how real estate brokers are selling the neighborhood to potential new residents of the luxury developments sprouting up among the area’s boarded-up buildings and expansive tracts of public housing.

The company that owns Hampton Court, a new building on First Avenue and East 102nd Street that also faces the East River Houses, includes the property among its listings in “Gracie Point” — the northern section of the Upper East Side that encompasses the mayor’s residence, Gracie Mansion. A real estate broker advertising a building going up on East 117th Street, the Nina, calls the area “the playground for the Sophisticated Bohemian” on its Web site.

A senior vice president at Corcoran Group Real Estate, Neal Sroka, said safety in the neighborhood is improving rapidly, despite a few “isolated incidents.”

“You’re going to have isolated incidents of violence anywhere in the city,” Mr. Sroka, who handles rentals at a new luxury building on East 114th Street and Pleasant Avenue over Rao’s restaurant, said. “Everything has improved. The police department has done an unbelievable job making the city safe.”

In East Harlem, as in the city as a whole, crime has dropped significantly in recent years. Once one of the main hubs of the crack epidemic of the late 1980s and early 1990s, the 23rd Precinct in East Harlem has experienced a 74% decrease in overall crime since 1990.

Yet this year, even as some categories of violent crime have continued to decline in the neighborhood, others such as rape and robbery have held steady. Almost halfway through the year, five murders have been reported. Last year, 10 murders total were recorded.

In recent weeks, a nonfatal shootout also took place in the Thomas Jefferson Houses, just a block away from the new Rao’s building.

Some residents say they hope the arrival of wealthy neighbors will bring better security and services, a suggestion that angers their representative in the City Council, Melissa Mark Viverito.

“Everybody deserves the same level of city services,” she said. “Nobody wants to live with violence.”

But one of the services already in place in the area to combat violence, Operation Impact, could be in danger. The program sends extra police academy graduates to certain precincts with high levels of crime, including East Harlem, and has been credited with helping crime rates to decline.

With the police department only able to fill a quarter of its openings this summer, Operation Impact could face cutbacks.

“I’m concerned about my community,” Ms. Mark Viverito said. “We need more foot patrol officers.”

Ms. Urena, who is going to school to become a real estate agent, said she is not waiting to see if things improve. “I would move before I had kids here,” she said. “I feel it’s unsafe.”

As newcomers snap up million-dollar condos up and down First Avenue, a 10-year resident of the East River Houses, Nidia Jaramillo, 70, said she has watched the recent violence drive other longtime residents out of the neighborhood.

“They have been moving,” Ms. Jaramillo said. Of the newcomers, she added, “I don’t know why they would invest so much money to live here.”