SAN DIEGO -- A just-completed undercover law enforcement infiltration of one of the city's largest street gangs resulted in 93 arrests and the seizure of an array of illegal narcotics, illicit drug profits and a small arsenal of firearms, authorities said Monday.

Those jailed during the five-month multi-agency investigation -- about half of them documented gang members -- are suspects in numerous crimes, including murder, robbery, pimping, and drug and weapons trafficking, according to San Diego police.

The arrestees include many of the the Skyline-area gang's top leaders, SDPD Chief William Lansdowne said.

Three of the suspects were allegedly involved drug sales at a South Bay day-care center -- which has been closed due to the purported crimes there -- and at a pizzeria in the eastern San Diego district claimed by the gang as its turf.

The crackdown, dubbed "Operation Red Sky," also netted 19 guns, 240 marijuana plants, 10 pounds of harvested cannabis, about 20 pounds of powder and crack cocaine, two pounds of methamphetamine, 18 vials of PCP, some 3.000 ecstasy tablets and roughly $60,000 in cash.

The effort and a half-dozen similar sweeps undertaken in the city this year have helped significantly reduce local gang crime, Lansdowne said during a Monday afternoon briefing outside downtown SDPD headquarters.

To augment the law enforcement strategy, the city has employed programs designed to keep youths from joining gangs in the first place, the police chief told reporters.

"We're using diversion, a hundred-percent increase in the amount of diversion, to really work very closely with the community of San Diego to make it the safest large city in America," Lansdowne said. "That's our goal. In the last five years, we've moved from (being) the ninth-safest city to the sixth-safest city in America."

Taking part in the probe along with San Diego police were the county District Attorney's Office and Probation Department; state Parole Department; U.S. Attorney's Office; U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives; U.S. Drug Enforcement Administration; U.S. Marshals Service; and Naval Criminal Investigative Service.