"They've been relieved of their police powers, and that will continue until this thing is resolved," he said.
Ramsey said two other narcotics cops linked to the probe were already off the street - Jeffrey Walker, who has been in federal custody since May, and Linwood Norman, Walker's partner, who was benched last week.
"This is a group that's been under investigation for some time," he said, adding that he couldn't divulge more information because of the grand-jury probe.
A police source said Ramsey met Thursday with federal authorities a few hours before he benched the five cops.
Liciardello, Spicer, Betts and Reynolds were transferred - along with Officer John Speiser and Lt. Robert Otto - from the Narcotics Field Unit in December 2012 after District Attorney Seth Williams sent a letter to Ramsey saying that they wouldn't be called to testify in drug cases because of concerns about their credibility.
At least 68 pending drug cases soon were withdrawn by the District Attorney's Office.
The Daily News found that the city has paid $777,500 to settle at least 15 lawsuits filed against those officers since 1999. The lawsuits accused them of offenses ranging from stealing to performing illegal searches and planting drugs on suspects.
Walker was arrested in an FBI sting in May while allegedly trying to steal $15,000 from a drug dealer's home in Kingsessing.
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