D.C. police said they broke open a "crack" cocaine ring during a series of 12 arrests yesterday in a Northeast Washington "open-air drug market," but they said that crack dealers have not penetrated deeply into Washington's illegal drug market.

Crack -- small, extremely potent rocks formed by purifying ordinary street cocaine -- is sold in vials and packets and is prevalent in a number of major cities, particularly New York, Detroit and Los Angeles. The crack sold in Washington comes mostly from New York City dealers who receive shipments from Bolivia and Peru, police said.

"What would sell for $15 in New York goes for $30 in Washington," said Capt. William White III, a police spokesman. "Oftentimes, the illicit-drug entrepreneurs will travel from New York to Washington and sell the drug here at a higher price."

White said one reason crack is more expensive in Washington is that the drug is more plentiful in the port city of New York. But he also attributed the high price in the District to low supply and a preference for other drugs. "The No. 1 drug of choice in D.C. is PCP," said White.

"Based on our investigations and surveys, we believe that PCP is more prevalent here because of the youthful clientele involved, which is between 15 to 25 years of age," White said.

During an eight-hour operation early yesterday morning, police broke open a crack ring operating outside the Mayfair-Paradise Manor apartment complex at 3693 Jay St. NE. The seizure netted $5,274 in cash, two stolen automobiles, 10 assorted guns and 109 rounds of ammunition, 10 lids of PCP with a street value of $6,340 and 233 vials of crack with a street value of $5,825.

"When you take into consideration the small concentrated area, 12 people locked up in an eight-hour period, the quantity of narcotics seized coupled with the number of weapons taken, it's a very significant operation," said White.

Eleven men and one woman were arrested during the operation and charged with various offenses, including firearms violations, being fugitives from justice, possession of cocaine, possession with intent to distribute cocaine and unlawful entry.

During one arrest, a police lieutenant fired at a 17-year-old youth from the Bronx, N.Y., who had pointed a handgun at the officer, police said. The shot missed. The youth was charged with assault on a police officer while armed, carrying a pistol without a license and violation of the controlled substance act, police said.

In November, four persons were shot to death in the same area, which police said is a growing drug market where rival drug groups with "enforcers" are staking out their claims. Two of the deaths occurred near a vacant apartment being used as a "crack house," sources said.

Police said they conducted the eight-hour drug watch in the area yesterday morning after complaints of drug activity from residents and observations made by officers.