Shuffling along an East Baltimore street, an undercover detective gave a knowing glance to a suspected drug dealer bundled in a thick coat outside a mini-mart on a painfully cold January morning.
In half a minute, the detective walked off with two $10 capsules filled with low-grade heroin. Other officers soon swooped in, arrested the alleged dealer, discovered a stash of 59 gelatin capsules of heroin and recovered the detective's marked $20 bill.
"You're captured, clown show," said Sgt. Stephen J. Kolackovsky as he took a photograph of the 23-year-old suspect with an instant camera for police records.
The operation took less than 30 minutes - from buying the drugs to sending the man to the Eastern District station in a police wagon - but the arrest could result in serious jail time. Charged with felony drug distribution, the alleged dealer will likely be indicted and could face up to 20 years in prison.
A year ago, such an arrest by an undercover officer would have been relatively rare in Baltimore. Police attacked the drug trade mostly with surveillance techniques that proved to be less effective in court.
In recent months, however, Police Commissioner Kevin P. Clark has increasingly turned to undercover drug purchases to reduce brazen dealing. He hopes the effort will quell the high level of violence that is tied to the narcotics trade, and help strangle a drug market that feeds the habits of the city's estimated 40,000 to 60,000 addicts.
In the past eight months, detectives carrying out Clark's strategy have made more than 6,000 felony drug arrests. Felony narcotic indictments by city grand juries jumped 28.6 percent last year - from 5,776 in 2002 to 7,427, many the result of about 2,100 undercover drug purchases.
"The tides are turning," said Anthony J. Romano, chief of the organized crime division, which has led the initiative since its inception in late May. Twenty-four undercover officers and 88 other detectives and supervisors in the division concentrate on street-level dealers.
"It's getting more difficult to make arrests on the streets," Romano said. "Dealers are showing more caution about who they are selling to."
That was apparent one afternoon last month when detectives in Kolackovsky's squad were roaming the Eastern District, a notorious haven for drug dealers, and an undercover officer got a tip about drug dealing inside a convenience store at Chester and Gay streets.
Once the detective was inside the store, the alleged dealer - a store customer - locked the door and asked to frisk his unfamiliar client, clearly concerned that he might be an undercover officer.
"Just joking," the man said before selling the detective a $10 pill of heroin.
Police officers later arrested the suspect and discovered a vial of cocaine in the seam of his underwear and five capsules of heroin in his jacket sleeve. They also recovered the marked $10 bill.
Such arrests are making life easier for prosecutors, who say that they yield better witnesses - police officers - and more evidence, especially the marked money.
"The cases are a lot stronger," said Salvatore Fili, chief of the narcotics division of the Baltimore state's attorney's office. "Your drug buyer is a police officer. His whole mission is to go out on the street, find a seller and interact with him, study him the entire time."
Judges agree. "It's a good first step," said Baltimore Circuit Judge John N. Prevas.
Previously, the agency's smaller group of undercover officers mostly investigated mid- and high-level drug organizations, police officials said.
Street-level drug enforcement was left largely to the discretion of district commanders, and their detectives often relied on tactics that led to quick arrests but resulted in little prison time, prosecutors said.
For example, officers often watched drug deals and made arrests based on their observations, sometimes allowing buyers to go free - losing a key piece of evidence that narcotics trafficking had actually occurred.
Although prosecutors and judges are optimistic, the undercover cases are so new that few have reached trial.
Also, the aggressive approach has not reduced the level of deadly violence in Baltimore, which recorded 271 killings last year, the city's first annual increase in homicides since 1998.
Police officials believe that the division's work will eventually start paying dividends, even though the dealers are still on the streets and have started changing their tactics.
Besides frequently asking detectives if they are undercover officers, some dealers have turned to hiding their stashes in houses. The division's detectives have responded by conducting more narcotics raids. The division served 78 search warrants in the first three weeks of January, up from a monthly average of about 60 last year, they said.
At least one man tried to evade capture by resorting to a self-service business - he would take cash from customers and have them pick up the drugs from another location. But the strategy didn't work - police arrested him on distribution charges, detectives said.
"We're making them more leery," Detective Kevin Baskette said, "and they are worried who they are selling to."