U.S. Park and District police launched an attack on illegal sales of the prescription drug Dilaudid during the last two weeks with three operations that produced 43 arrests and the seizure of several hundred pills of the drug, a popular heroin substitute.

Dilaudid is sold mainly at 11th and O streets NW and the surrounding blocks in the Shaw neighborhood. Street-level dealers hawk the tiny, yellow pill as "D" or "K-4," referring to the manufacturer's stamp on the 4 mg pill.

On Wednesday and Thursday the Park Police vice squad arrested a total of 10 people, most of whom were charged with possession with intent to sell Dilaudid. They said two of them were high-level distributors of the pill.

On July 19, D.C. police closed an investigation into sales of the pills around the Garnet-Patterson Junior High School at 10th and U streets NW with the eventual arrest of 33 people.

Selling Dilaudid is a lucrative business. The pill, if bought legally from a pharmacist, costs about 50 cents. In Washington it sells for about $40 on the streets. Police estimate that 200 to 400 are sold daily on the streets of Shaw.

Dilaudid, often prescribed as a painkiller for cancer victims and post-surgical patients, becomes illicit when diverted from legal channels to street sales. It reaches the street market in several ways, according to Tom Gitchel, chief of the diversion operation for the U.S. Drug Enforcement Administration.

"Sometimes a doctor or a pharmacist will sell the drug," said Gitchel. "Then we have some doctors who write indiscriminate prescriptions because they are the victims of scams or they are not knowledgeable about the drug. Dilaudid is sometimes stolen from pharmacies. And then we find some people printing their own prescription pads or stealing doctor's pads."

Gitchel said that in some cities, entrepreneurs have taken cancer patients from doctor to doctor to get Dilaudid prescriptions.

"They will tell the doctor that they are on vacation and forgot their pills back home," said Gitchel. "The doctor has done nothing wrong by writing the prescription."

The pills, once obtained, pass through several hands before reaching the buyer. In the typical scenario, according to Lt. Hugh Irwin, who heads the Park Police vice squad, the person who either stole the pills or got them through prescriptions sells them to a "wholesaler" for a profit of $5 to $10 per pill. That person sells the pills at a similar profit to a "distributor," who passes them on to the street dealer for the same profit margin.

Irwin said the dealer can sell directly to the customer but is more likely to go through a "juggler" or "runner" who usually gets paid $5 for making the sale. The dealer and juggler run the greatest risk of arrest because they do their business right on the street, he said.

All day and most of the night, O Street between 9th and 13th streets NW is crowded with men who flash the four-finger sign to indicate they have Dilaudid for sale. There are so many sellers that some are bold enough to approach drivers stopped for traffic lights.

Following the police operations in the area, the dealers along O Street became less aggressive, choosing instead to hang back in doorways waiting for known customers. Last night, however, a few returned to the street to signal passing cars.

Police say the usual customers for Dilaudid are white suburbanites who are highly visible in the mostly black neighborhood of Shaw.

Lt. James Dotson, head of the 3rd District vice squad, said his squad has been so successful in disrupting the Dilaudid market near Garnet-Patterson that white customers with Maryland and Virginia tags can be seen repeatedly circling the school looking for dealers. "There is very little drug business at the school right now," said Dotson.

Irwin said he and his officers have succeeded in curtailing the Diluadid sales in the 11th and O streets area as evidenced by the lack of business at that location.

"We know there will continue to be a market there as long as people are greedy," said Irwin. "People get used to making that money and they will go right back to dealing when they locate a supply of pills."

One of Irwin's officers, more optimistic than his boss about eliminating the Dilaudid market, left a hand-lettered sign in the window of an alleged distributor who police had just arrested.

The sign read: "CLOSED BY ORDER OF THE UNITED STATES PARK POLICE! No "D's" Today, Tomorrow, Forever!"