Federal prosecutors are looking into a February incident when a Camden County police officer was caught on camera punching a man 12 times in the head.

The attorney for Edward Minguela, 32, of Camden, has demanded criminal charges be filed against the officer he said threw the punches: Nicholas Romantino, a 24-year-old who has been on the job for less than two years.

Camden County Police Chief J. Scott Thomson said he was "extremely disturbed" by the video and has suspended the officer without pay while the county prosecutor investigates.

But the county revealed Friday that the case is also being investigated by the U.S. Attorney's Office of New Jersey.

The information came out when the county was denying an OPRA request for body camera footage, claiming it was exempt due to the ongoing federal investigation.

Camden County Prosecutor's Office spokeswoman Alexandra McVeigh said Friday that the prosecutor is still investigating the incident. She declined to comment on the feds' involvement.

It's the latest development in the case that came to light in late February, when Minguela posted the surveillance video of his own beating on his Facebook page.

Minguela told NJ Advance Media that he was walking away from Fairview Liquors on Collings Road Feb. 22 when police ran up with guns drawn and told him to put his hands up. They were responding to a 911 call about a man with a gun, and he matched the description, according to the county.

The surveillance video, which Minguela said he obtained from the liquor store, shows him holding his hands up as an officer approaches him and takes him to the ground. He then punches Minguela 12 times in the head while two other officers appear to hold him down, and others look on.

Police never found a gun on Minguela, but they charged him in municipal court with resisting arrest and obstruction.

He claims officers took him to the hospital but told him there that if he told hospital staff he needed treatment, they would also charge him with the more serious offense of assaulting a police officer. Minguela said he followed officers' instructions and declined medical care, but he went back to the hospital the following morning.

His attorney, Devon Jacob of Pennsylvania, said his client was treated for a concussion and a fractured wrist.

"I look forward to learning the outcome of the police department's internal investigation, and the state and federal criminal investigations," Jacob said in a statement Friday. "These three independent investigations will undoubtedly reveal the disparate treatment, and the malicious intent of the prosecutor's office, in continuing to violate Mr. Minguela's civil rights by refusing to dismiss the frivolous criminal charges."

Last week, McVeigh said the prosecutor's office had stayed the charges against Minguela while it continued investigating.

Chief Thomson said he was aware that someone had requested that county, state and federal officials look into the matter, but said he could not comment on any ongoing investigation other than to say that the police department is cooperating.

"I was extremely disturbed by what I saw on the video," Thomson said in a statement Friday. "The observed actions are completely contrary to how we train our officers and the culture of this organization and will not be tolerated."

Jacob and the Camden County chapters of the NAACP have called for Romantino to be charged and fired and for the Attorney General's Office to investigate. While Romantino is suspended without pay, the other two officers involved are on paid leave.

Matthew Reilly, spokesman for the U.S. Attorney's Office in New Jersey, said he could not confirm or deny that the office was investigating Romantino, per office policy.

No federal charges have been filed against Romantino, who earns a salary of $41,158.

Rebecca Everett may be reached at reverett@njadvancemedia.com. Follow her on Twitter @rebeccajeverett. Find NJ.com on Facebook.

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