Hours before ATF agents raided his home and arrested him in 2005, Philadelphia drug kingpin Alton "Ace Capone" Coles got a phone call from a friend in California warning that "the feds were coming."

Federal authorities now believe the friend's source for that tip was a Philadelphia police detective.

The detective, Richard "Rickie" Durham, was working with a 200-member task force that was poised to execute a series of raids that would take down Coles and most of his top associates on Aug. 10, 2005, capping one of the most significant drug investigations in recent Philadelphia history.

Durham, 43, is now the target of a federal grand jury investigation, sources said. Contacted at his home last night, Durham denied that he had done anything improper, but confirmed that he had been placed on restricted duty because of the allegations.

"They're false allegations," said Durham, a 12-year veteran assigned to the major-crimes unit who was working on a temporary assignment for the FBI at the time of Coles raid. "I'm not worried. . . . It should work out to my favor."

Durham said he had made a phone call to a friend in California that night "trying to ascertain some information" about Coles' girlfriend, Asya Richardson.

"He must have read through it," said Durham, meaning the friend was able to tell from the questions that an arrest was about to take place.

Federal authorities declined to comment yesterday. "I can neither confirm nor deny," said Assistant U.S. Attorney Richard Lloret.

Lloret and Assistant U.S. Attorney Michael Bresnick prosecuted Coles and his top associates, most of whom were convicted. Coles, 35, was sentenced to life plus 55 years at a hearing last month.

The onetime Southwest Philadelphia rap-record company executive was questioned about the phone call during his drug-trafficking trial back in February 2008.

A phone call

Coles, who took the stand in his own defense, acknowledged that he had gotten a call about 2:45 a.m. on Aug. 10, 2005, from California.

He said the caller told him "the feds were coming."

When asked who had called, he said, "I forget. Somebody named Tee."

Asked by Lloret if the call had come "just out of the blue," Coles replied, "Yeah."

Coles was then living with Richardson in a $480,000 home outside Mullica Hill. They had moved in about 10 days earlier.

The raids scheduled for that morning were to cap a two-year task force investigation run by agents for the the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF).

Durham was one of more than 200 law enforcement agents assigned to help carry out those raids, which occurred at more than a dozen locations in Philadelphia, South Jersey, and the Pennsylvania suburbs.

Officer briefed

At the time of the raid, Durham was a "task-force officer" for the FBI, a common arrangement in which a local police officer is deputized to work side by side with federal agents.

Neither he nor the FBI was involved in the Coles investigation, but both were briefed on the raid the day before, because they were part of a group of federal agents lending assistance.

ATF agents, who had taps on some but not all of Coles' phones, heard the drug kingpin make several calls early that morning, including several to another girlfriend, Monica Pullins, who lived in an apartment in North Philadelphia that investigators believed was a drug stash house.

Coles made eight phone calls to Pullins between 3:07 and 3:50 a.m., urging her to get rid of the "black thing" he had left in the apartment.

Agents believed that was a reference to a handgun they later recovered in the apartment's trash bin. They later said the phone calls were disturbing because it appeared Coles had been tipped off about the pending raids.

Nearly $1 million in cash, more than a dozen weapons, and more than a kilogram of cocaine were seized.

Desk duty

Durham said last night that he did not know Coles, but was a longtime friend of a man he described as Richardson's "estranged half-brother." He said he called him that night as part of the investigation.

Durham began his FBI stint in September 2003 and was stripped of his temporary federal powers last year when he became a suspect in the case. He has been assigned to desk duty with the Philadelphia Police Department's major-crimes unit.

The status of the California man - whether he is a witness or a suspect - could not be confirmed last night. The Inquirer is withholding his name because he could not be reached for comment.

The Durham investigation is the latest allegation of corruption involving Philadelphia police officers working narcotics cases.

Jeffrey Cujdik, a member of a narcotics field unit, has been placed on desk assignment while authorities investigate allegations that he fabricated informant information to justify arrests and narcotics seizures. Two other narcotics officers have also been assigned to desk duty - but not relieved of their weapons or police authority - because of the probe.

And former officer Malik Snell has been tried twice on federal charges that he used his badge to rob drug dealers. Both trials have ended in hung juries.

Coles and five codefendants, including girlfriends Richardson and Pullins, were convicted last year after a six-week trial.

Authorities alleged that Coles and his top associate, Timothy "Tim Gotti" Baukman, used their record label, Takedown Records, as a front for a multimillion-dollar cocaine-and-crack distribution network.

At Coles' sentencing hearing last month, Lloret estimated that the Coles drug network brought more than two tons of cocaine and nearly a half-ton of crack into Philadelphia between 1998 and August 2005.

Richardson and the other codefendants in the Coles trial are awaiting sentencing.

Keenan Brown, a codefendant tried with three alleged Coles associates at a separate trial, was sentenced yesterday to life in prison.

Read "The Takedown of Ace Capone," a two-part series on how investigators built their case, at http://go.philly.com/aceEndText

Contact staff writer George Anastasia at 856-779-3846 or ganastasia@phillynews.com.