17 Philadelphia police officers suspended over social media posts originally appeared on abcnews.go.com

The Philadelphia police commissioner has suspended 17 officers for 30 days and is moving to fire 13 of them over social media posts he called "sickening.".

Police Commissioner Richard Ross made the announcement during a news conference Thursday attended by Philadelphia Mayor James Kenney and the entire police department's command staff.

"I continue to be very angered and disappointed by these posts, many of which, in my view, violate the basic tenets of human decency," Ross said. "And I am saddened by the fact that there are even some who would attempt to justify such hateful and vile behavior."

PHOTO: Philadelphia Police Commissioner Richard Ross speak during a news conference in Philadelphia, July 18, 2019. (Matt Rourke/AP) More

The disciplinary action stems from research published by the watchdog group the Plain View Project, which examined more than 3,100 allegedly troubling posts made by 328 active Philadelphia police officers, 72 of whom were put on administrative duty.

Ross said an investigation by an outside law firm contracted by the city found that the officers being suspended allegedly made racist, transphobic and otherwise hateful posts.

The police department immediately launched an internal investigation on June 1 when agency officials were made aware of the questionable social media posts, according to Ross.

He added that most of the 72 officers who had been pulled off street duty posted material "which advocates excessive force, but not necessarily to a person's membership in a protected class." He said such posts violated the city's social media directive by posting statements that "erode the trust necessary for a police department to carry out its core mission."

PHOTO: Philadelphia Mayor Jim Kenney, accompanied by Police Commissioner Richard Ross speak during a news conference in Philadelphia, July 18, 2019. (Matt Rourke/AP) More

(MORE: Philadelphia police under investigation amid claims of racist, offensive social media posts)

Ross said officers who fell into the less egregious category will receive discipline ranging from a reprimand to a five-day suspension.

"The second group of officers posted material that is not only offensive and unprotected but constitutes an act or continuing course of conduct which demonstrates that the officers have little or no regard for their position as police officers," Ross said.

He said the 17 officers who allegedly fell into that category will be suspended for 30 days, and the department will move to dismiss 13 of them.

(MORE: Over a Crock-Pot: How seemingly minor interactions with police spiral out of control)

The Philadelphia Fraternal Order of Police, whose president previously opposed disciplinary action being taken against officers involved in the scandal, posted a statement on the union's website on Thursday, saying, "No member should agree to any discipline nor sign anything without first contacting the FOP."

Commissioner Ross said the officers facing the harshest discipline allegedly posted anti-Islamic statements such as "Death to Islam," used slurs to describe African Americans, encouraged police brutality, and posted homophobic memes suggesting "violence against transgender individuals."

"These posts undoubtedly have a profound impact on our police-community relations in this city, and, arguably, have an impact on the profession," said Ross, who did not release the names of any of the officers being punished.

He said most of the 72 officers allegedly involved in the offensive social media posting went through training on June 28 on social media and professionalism and will be required to complete more training on those subjects.

Ross also said the department will purchase or develop a proactive mechanism to audit officer-related social media and identify potential problems, and that all officers will have to go through anti-bias training sometime in the fall.

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