One of the ways reformers are trying to reduce the use of excessive police force is by requiring police officers to wear body cameras. Cities like Cleveland are moving toward requiring more officers to wear cameras to ensure accountability.

But a case out of Denver shows that not all police are so keen to be recorded. This past August, a group of police officers attempted to arrest David Nelson Flores for suspected drug possession. When he stuffed a sock in his mouth and refused to open his mouth, one of the officers struck him in the head repeatedly. “Those were the hardest punches I have ever heard, said Levi Frasier, a bystander who witnessed the beating.

But police did not limit their use of force to Flores. They also tripped his girlfriend, who was almost eight months pregnant at the time. Luckily for Flores and his girlfriend, Frasier recorded the entire incident on his tablet. But the police took his tablet and deleted the video. At least they thought they deleted it. When Frasier got home he discovered the video file reappeared once the tablet synced with the cloud server.

The FBI's Public Corruption Unit is invesigating the use of excessive force and a possible illegal search of Frasier's video files.

Watch the clip below: