By Tony Hanson

PHILADELPHIA (CBS) A former Philadelphia police narcotics officer today pleaded guilty to corruption charges.

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Former officer Jeffrey Walker is at the center of continuing grand jury investigation.

Today, the court proceedings confirmed what multiple sources have told KYW Newsradio previously: that he has been cooperating with authorities since shortly after his arrest in May of last year.

Walker, then a 23-year veteran of the Philadelphia Police Department, was arrested after he planted drugs in a suspect’s car, stole a house key, then went to the target’s home and stole approximately $15,000.

He was arrested leaving the house and, the FBI reports, he confessed immediately.

This morning Walker’s defense attorney, Thomas Fitzpatrick, said he expected a “significant” number of indictments to come as a result of his client’s cooperation with prosecutors and a “significant” amount of corruption within the Philadelphia Police Department to be exposed.

Prosecutor Anthony Wzorek told the court that Walker has agreed to tell of any other crimes of which he has knowledge, and to testify at future proceedings if called upon by the government.

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How many others might be implicated by Walker’s future testimony?

“More than I can count at this point,” Fitzpatrick said.

Fitzpatrick said his client’s wrongdoings were small potatoes compared to what he would help prosecutors uncover.

Sources also say Walker has implicated other officers in alleged robberies.  His information led to a search of the Schuylkill River last year for a stolen safe allegedly discarded there.  It was not found.

In January, Philadelphia police commissioner Charles Ramsey acknowledged the federal grand jury investigation when he announced a total of six officers had been removed from street duty.  The officers have surrendered their badges and guns.

Those six officers have not been charged.

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