In the latest blow to the Philadelphia Police Department's embattled narcotics unit, federal authorities have arrested a veteran officer and accused him of stealing money and drugs from a suspected dealer.

Officer Jeffrey Walker was taken into custody Tuesday by FBI agents after a sting operation in which they recorded him bragging about how easy it was to rob dealers.

In a complaint filed in federal court Wednesday, authorities said they had recorded conversations between Walker and a federal informant in which they discussed a plan to plant cocaine in a suspect's car and later rob him. Walker arrested the suspect, then he and the informant entered the suspect's house and stole $15,000 in cash, the complaint said.

As the two left the house, FBI agents and members of the police Internal Affairs Division moved in. According to an FBI affidavit, Walker was carrying the cash when he was arrested.

Agents said Walker and the informant eagerly plotted to rob drug dealers. All the while, unbeknownst to him, the FBI was listening in.

In a conversation recorded May 6, Walker described how he could stop a suspect's car, confiscate drugs, and keep most of them for himself. He and the informant then mapped out a plan to rob a dealer who drove a black Volkswagen Jetta.

On Tuesday, as the FBI looked on, Walker approached the Jetta and appeared to plant something inside, the affidavit said. Later, as the suspect drove away, Walker followed.

He and other officers quickly stopped the Jetta, found drugs, and arrested the suspect.

Late that night, Walker and the informant went to the suspect's house, which was under surveillance by the FBI and a team of investigators from police Internal Affairs, and stole the money.

After his arrest, Walker admitted taking the $15,000, the affidavit said.

Lt. John Stanford, a police spokesman, said the arrest was an example of "us policing us."

The team of federal agents and city officers that arrested Walker is the same one that investigated six narcotics officers who were transferred from the field unit in December. Since then, the District Attorney's Office has withdrawn about 300 prosecutions involving the six - who are still working for the department in lower-profile jobs.

Walker appeared Wednesday before U.S. Magistrate Judge Thomas J. Rueter and is being held in federal custody. His next court appearance is May 28.

Walker has been assigned to the narcotics unit since 1999. Police Commissioner Charles H. Ramsey has placed him on a 30-day leave of absence with intent to dismiss, police said.