D.C. police said yesterday they had broken up an unusual "dial-a-dope" drug ring in which customers ordered heroin by phone and then met delivery people to make their purchases, thus eluding police street surveillance.

Police arrested 17 persons from the District and Maryland, including two D.C. firefighters and a Department of Energy financial analyst, and charged them in connection with the "dial-a-dope" drug ring, D.C. police Capt. James Nestor said at a press conference yesterday.

Nestor said most of those arrested Wednesday were part of a multimillion-dollar drug operation once run by Joseph McCrea, who was shot and killed in November at his Southeast home by someone dressed as a mailman. At the time, police said a search of McCrea's house uncovered $2 million in drugs, cash, furs and jewelry and an address book that indicated he had an elaborate network of drug and other contacts in this country and abroad. No one has been arrested in McCrea's shooting.

Police said they learned of McCrea's operation a month before he was fatally shot. Police said that their continued investigation, which included telephone surveillance, showed that an operation similar to McCrea's had been set up. James Roland Shaw, 28, of 101 G St. SW, whom police identified as an employe of McCrea, was the leader of the operation, according to Nestor.

Shaw was arrested Wednesday and charged with conspiracy to distribute a controlled substance. Among those arrested on the same charge were: Joseph P. Robinson, 33, a Department of Energy financial analyst who lives at 4248 Suitland Rd., Suitland; and Carlton Tyrone Clemons, 41, of 5018 Silver Hill Rd., Forestville, a 15-year District firefighter with Engine Company 7, and James Henry Carter, 31, of 1106 Owen Place NE, a student firefighter who was hired just over a week ago, said fire department spokesman Ray Alfred.

Carter will be dismissed immediately, said Alfred, while a "notice of proposed suspension" will be sent to Clemons. If Clemons is suspended, a trial board will investigate and recommend whether or not to terminate his employment, he said. "Based on what I understand, all of the transactions happened in the street and no drugs were sold at the fire station," said Alfred.

"We don't know if this is a new way of eluding us," Nestor said of the telephone operation. "Everything was done by phone. The exchanges were very quick." He said the heroin was also of a high quality.

Through court-ordered wiretapping last month, police were able to track phone calls from customers using pay phones as well as phones from government offices. "They would usually call an office, an apartment that Shaw had rented," said Sgt. Allen Marshall, who supervised the investigation. "The caller had to identify himself and be known. The person at the office would give the location and the price."

Police believe the ring had been operating at least five years. Five of those arrested are Maryland residents and 12 live in the District. Police said more arrests are expected.