Federal law enforcement authorities, culminating a two-year investigation during which undercover agents traded cellular telephones and pagers for crack cocaine, arrested 23 people yesterday who are alleged to be members of a large-scale drug distribution network in the District and suburban Maryland.

The phones supplied by an undercover FBI agent then became the tools by which investigators listened to the accused drug dealers arrange transactions, according to a federal affidavit. Typically, according to the affidavit, the alleged drug dealers bought the cellular telephones with an ounce to two ounces of crack cocaine and paid for their monthly bills with another ounce of cocaine.

An FBI agent represented himself as an employee of a cellular telephone company, enhancing several deals by telling the alleged drug dealers that the cellular telephones could not be tapped, law enforcement sources said.

The 23 arrests stemmed from indictments unsealed yesterday that charged 29 people, many of whom lived in the Woodridge neighborhood in Northeast Washington, with conspiracy to distribute cocaine and crack. Among the most well-known members of the loose-knit organization, dubbed the Woodridge Group by investigators, were convicted drug dealers Brian Tribble and Ricardo Smith. Smith and Tribble were not indicted.

Authorities said the organization moved upwards of five kilograms of crack cocaine a week, based on wiretapped conversations and seizures.

The phones proved popular with the alleged drug dealers, who feared their home telephones might be tapped and were afraid of getting shot while using public telephones.

"I don't like getting out in them phone booths," Paul Winestock Jr., one of the men indicted, told the undercover agent when arranging for a phone, according to an affidavit.

Law enforcement authorities would not discuss wiretapping methods for cellular or standard phones, both of which were used in the investigation.

Pages of wiretapped conversations recounted in the federal affidavit show that several of the people indicted soon became comfortable with the cellular phones.

Winestock continued to talk freely on the cellular phones despite a warning from an unknown man that there should be no more "talkie-talkie," according to the affidavit.

During one particularly humorous series of wiretapped telephone calls on Oct. 17, Norman O'Neal Brown, who also was indicted, discusses an FBI search of a co-defendant's car during which more than a pound of cocaine was found, according to the affidavit. Brown advises his friend to call police and say that his car was stolen while he was playing basketball in a "drug-infested area," according to the affidavit.

Arrests also were made in Prince George's County, Baltimore, Virginia and Philadelphia, authorities said.

Tribble and Smith are mentioned frequently in a 228-page federal affidavit that recounts drug transactions and wiretapped telephone conversations. Tribble pleaded guilty to a charge of conspiracy to distribute cocaine in October and is awaiting sentencing; Smith is serving an 18-year sentence.

Tribble's name became a household word in 1986 after he was accused -- and acquitted -- of supplying University of Maryland basketball star Len Bias the cocaine that caused his death. Bias's death from a cocaine overdose days after his draft by the Boston Celtics rocked college athletics.

"It would be inaccurate to say that Brian Tribble was a leader of this group, but certainly he was an active player," said Assistant U.S. Attorney E. Thomas Roberts. "Brian Tribble grew up with all these people and certainly was one of the individuals who supplied cocaine to them."

Law enforcement sources and Tribble's lawyer, Thomas C. Morrow, said that Tribble did not cooperate with the investigation, which essentially was completed before his guilty plea on Oct. 19.

Staff writers Gabriel Escobar and Paul W. Valentine contributed to this report.