CHICAGO — Driving past a street corner adorned with three spray-painted tributes to young men shot and killed on the streets, Chicago police officers jumped out of their cars and pulled a suspected drug dealer from an apartment.

The scene that played out Thursday morning is a result of an initiative that Mayor Rahm Emanuel announced last month that calls for dozens of officers from several specialized units on West Side and South Side Chicago, which account for a quarter of the city's homicides.

For weeks, the undercover officers have been buying heroin in this West Side area, while other officers have been watching to see where the seller goes, whom he pays, who hands him more drugs and what that person does with the drugs and money he's handed.

That led to 17 arrest warrants for people suspected of dealing drugs in the neighborhood and on Thursday — with The Associated Press and a local television station in tow — they went out to round up suspects. By Thursday afternoon, they said the roundup that began a few days ago had led to the arrests of 11 of the 17 suspects. Most of them were arrested on drug conspiracy charges.

"The key is to get them working in concert," said James O'Grady, the commander of the department's narcotics division, who likened the operation to a grocery store where a manager oversees the clerks and baggers. He said it doesn't matter if they are selling one bag or 50, "they're all part of the conspiracy."

And that, he said, means more prison time than had they been arrested simply for possession for sale.

Police Superintendent Garry McCarthy, who announced the initiative with Emanuel, said the areas where police would focus their attention were those that have seen both a thriving illegal drug trade but the worst gang violence.

Thursday's roundup followed a similar one targeting gang members late last month, and police say that by targeting those areas they hope that they will drive down violent crime, an issue that has become of particular concern as statistics from late 2011 and January of this year have shown an increase in homicides.

The lethal mixture of drugs and violence was as obvious as the words scrawled on the sidewalk outside the house where one of the suspected drug dealers was captured.

"They worked on this corner, they did," said Adolph Leggin, 66, motioning to two of the three names he recognized as local drug dealers who were shot to death last year.

McCarthy has said that the undercover operations would be part of a wider effort that will include more uniformed patrols, including foot patrols, in areas to make sure the open-air drug markets don't reestablish themselves.

That is a marked difference, he said, from the department's since-disbanded Targeted Response Unit, when the Mobile Strike Force would swoop into the neighborhood, make arrests and then leave.

O'Grady said residents will now see that the police are committed to their neighborhood.

"We want them to know we're not just an occupying force, (that) we are there every day, that they can depend on us," he said.

The effort is just a few weeks old, clearly not enough time to determine if what is being done will bring down the crime rate in a significant way as Emanuel and McCarthy hope it will.

Tio Hardiman, executive director of CeaseFire, an anti-violence group, was skeptical that the effort will have the long term effect on the targeted neighborhoods.

"It's been tried before and we wish police the best," said Hardiman. "At the same time we have to have other solutions than just increased police presence and mass arrests."

But Leggin said he is encouraged by what he's seen so far in the weeks since police focused their effort on the community where he's lived for more than 50 years.

"I come home now and I see nobody (dealing drugs) on this corner," Leggin said.