FBI investigating police K9 attack on black man during arrest

The FBI is investigating the Woodson Terrace Police Department in St. Louis County, Mo., after a video went viral that showed a black man being bitten by a police dog while being detained.

The video shows the suspect with his hands on the hood of the police car when the dog is released and starts biting the man's foot. Two officers bring the suspect to the ground as the dog continues biting.

After the dog is taken off the man, he gets up and starts running, until the dog is released on him again, biting the suspect and causing him to fall on the ground. As police appear to handcuff the man, the dog is taken off of him.

The police department is "fully cooperating" with federal investigators and the St. Louis County prosecutor's office, Woodson Terrace Police Chief Randy Halstead told the St. Louis Post-Dispatch.

The FBI often investigates color of law cases, where government officials have allegedly committed constitutional violations, such as excessive or unreasonable force by police, according to the news outlet.

The episode started when police responded to a call Monday morning that a man had broken into a business, the Post-Dispatch reported.

According to a police statement, the suspect appeared to be on drugs as he threatened officers, saying he was a "sovereign citizen," meaning that he doesn't believe he must follow government laws.

Police said the man was arrested but refused to comply with commands, and told if he continued resisting, the dog would be released on him, the Post-Dispatch reported.

"The suspect continued to resist, causing minor injuries to one of the officers so the K-9 was released and the K-9 gained control of the suspect's foot," according to police.

The man was then transported to a nearby hospital in an ambulance and was released from police custody pending charges.

The Post-Dispatch has not released the suspect's name as he has yet to be formally charged with a crime.

On Friday, protestors gathered outside the Woodson Terrace Police Department, demanding the three officers involved be fired and prosecuted.