ANTIOCH, Calif. (KGO) -- There was a violent arrest in the East Bay that was caught on camera Tuesday afternoon. Some witnesses say it was a case of police brutality, but the other major issue could be what happened when the cameras were turned off.The arrest at Contra Loma Boulevard and Buchanan Road was recorded by multiple people, but when police spotted the cameras, witnesses claim officers confronted them.This brings up some interesting questions about the rights of people and their video versus the rights of the police and whether or not they can take away that video.The Antioch Police Department declined an on-camera interview and all three witnesses that spoke to ABC7 News said they were afraid to reveal their identities because of what they saw police do to the man being arrested.On some of the video posted to YouTube you can hear a witness saying, "I don't think that's necessary."The first witness told ABC7 News, "I thought it was overkill. I was disgusted by it."Several witnesses say the man, who appeared to be mentally disturbed, was handcuffed while police used a Tazer on him and hit him with a baton. Then, they say, an officer released a police dog that began biting the man until he was bleeding and unrecognizable.The first witness continued to say, "Not his legs and his arms, his face and his head! That's doing too much."A second witness ABC7 News spoke to says officers began confiscating cellphones from anyone who shot video of the incident. An officer asked for his cellphone after he shot video and the witness said, "Then he took my phone anyway because I didn't want no problems. He emailed the incident to his phone."The first witness said, "They didn't take no for an answer apparently because they pulled one lady out of her vehicle to get it, and she wouldn't give it up and they were about to arrest her and finally they let her go because I believe she gave it up."However, a third witness told ABC7 News he was ordered to erase his video. So he did. He said, "They were being kind of controlling, like demanding, 'erase your phone' and they were trying to take people's phones away."The American Civil Liberties Union says police officers may not confiscate or demand to view your digital photos or video without a warrant.Antioch police told ABC7 News in a statement, "If a person is not willing to turn it over voluntarily, an officer can sometimes seize the device containing the video. The police would have to get a search warrant to retrieve the video from the device."Antioch police would not comment on the details of the incident.