Chicago Police Superintendent Eddie Johnson placed an officer on desk duty Tuesday after a video emerged that appears to show the officer kicking a suspect in the head during an arrest.

Johnson's order came the same day as media reports about an FBI email that was sent Nov. 24 about an infamous police video of a white officer shooting black teenager Laquan McDonald 16 times. The FBI warned the Chicago Police Department that day — hours before the video was released to the public, sparking days of protests — of a possible plot by gang members to ambush officers outside of two offices on the city's West Side.

In the email, the FBI said that a credible confidential informant had reported that gang members planned to open fire when CPD employees walked to their cars, when officers were particularly vulnerable in part because they were less likely to be wearing bulletproof vests. The FBI also said the gang members had discussed shooting and killing officers in their squad cars. There were no reports of any ambushes.

The latest video posted online, which prompted Tuesday's action, shows the suspect on the ground with an officer on top of him. A second officer then approaches and stomps on the suspect's head. The suspect was arrested after officers chased him and found three bags of heroin on him Monday afternoon, Chicago police spokesman Anthony Guglielmi said.

Charges are pending against the suspect. Police have not released the identities of the officers involved.

Terrance Hobson said he shot the video that was posted on Facebook on Monday afternoon. The agency that investigates Chicago police misconduct, the Independent Police Review Authority, started investigating Monday night, IPRA spokeswoman Mia Sissac said.

"It's still very early on," Sissac said. "We immediately went over to district to try and identify the officers and move forward from there."

According to a police report, the man bit the officer on the right ring finger before he was handcuffed. Guglielmi said the officer was treated for the bite at a hospital and the suspect also was taken to a hospital for treatment.

Guglielmi says Johnson has removed the officer's power of arrest.

"Since his appointment, the superintendent has stated that accountability begins with him down to the last police officer and that he will tirelessly work to rebuild public trust in the Chicago Police Department," Guglielmi said.

The Fraternal Order of Police said it disagrees with Johnson's decision to strip powers before IPRA has completed its investigation.