SAN FRANCISCO -- San Francisco police Chief George Gascon Friday announced a major personnel shakeup of the department's crime lab in the wake of alleged cocaine skimming and sampling by a technician that has forced the dismissal of at least 180 drug cases.

In a prepared statement, Gascon said the changes were not punitive but intended to enhance the transparency of the investigation. Both the commanding officer of the crime lab and the lab manager are being temporarily reassigned to other duties.

A source familiar with an official audit done of the lab, said the investigation may spread to other employees other then former technician Deborah Madden.

Gascon told KTVU he would take whatever action he deemed necessary.

"The outcome will be what the outcome (of the investigation) is,” he told KTVU. “If we have other people who have done something wrong, we will make that public and we will deal with it."

Gascon last week ordered drug testing at the lab temporarily halted after revelations that Madden, may have taken small quantities of cocaine from evidence jars.

Madden has not been charged, but an investigation into the allegations is still ongoing.

Drug testing has been outsourced to other crime labs pending the results of an internal police investigation into lab policies and practices, and an external audit led by the forensic services divisions of the state Department of Justice and the Sacramento District Attorney's Office.

Gascon said that crime lab commanding officer Capt. John Goldberg would move to the department's training division, and crime lab manager James Mudge would be assigned to a project relating to the department's automated fingerprint identification system.

Assistant Chief Jeff Godown will take overall responsibility for the investigation into the lab's practices, Gascon said.

The changes were expected to last three to six months, according to Gascon.

Police spokeswoman Lt. Lyn Tomioka reiterated that the changes were "absolutely non-punitive."

Replacing Goldberg will be Ingleside Station Capt. David Lazar, who will be assisted by Lt. Douglas McEachern, neither of whom have worked at the lab, according to Tomioka.

"Changes are being made so the perception for everybody -- the public, department members -- is that this is a fair and impartial investigation, and will be done in a timely manner," Tomioka said. "But the chief wants to identify all of the problems, and do one very thorough investigation that can identify everything."