That man, Daniel Saunders, resisted arrest, according to police. But Saunder's attorney claims the officers beat his client for no reason.

The dispute has prompted the Seattle Police Department to launch an internal investigation.

The disturbing footage shows Saunders standing at a South Seattle police station. In June, Saunders stopped by to pick up his belongings the day after a judge released him from jail.

Saunders is seen opening the door for three officers, the moments later, being punched times over by a police officer. The video then shows police hitting saunders with baton, allegedly because he was resisting arrest.

Saunders had been arrested a few days earlier after he broke through the window of the South Seattle church with his naked body and contaminating the interior with his HIV-positive, hepatitis C-tainted blood. Investigators said he caused more than $100,000 in damages at the Unity Church of God in Christ.

But Saunders had been released just a few days later as a result of a miscommunication. Charging papers failed to make its way through the system, prosecutors said, and suspects must be released after 72 hours if there are no charges filed against them.

The mishap prompted the issuance of a felony arrest warrant, under which officers tried to arrest Saunders when he went to pick up his belongings that had been confiscated at the time of his initial arrest.

But Saunders, who was armed with a screwdriver, violently resisted the arrest and tried to take the officers' baton, Taser and gun belt, according to the statement of probable cause. Officers eventually wrestled him to the ground and handcuffed him.

Saunders' lawyer, Andrew Magee, refused to comment on that point, but said he's more concerned about the events that led up to the incident.

Magee said Saunders shouldn't have been arrested for the second time in the first place. What Saunders didn't know was that he had been released due to a communication error and, as a result, was a wanted man.

"He was released, unconditionally, by way of a court order signed by a judge from jail, with no condition on his release placed on him and without violating any new law," he said.

The Seattle Police Department has launched an internal investigation to determine whether the officers used excessive force.

After his second arrest, Saunders subsequently pleaded guilty to breaking into the church, as well as resisting arrest during the contentious incident at the evidence unit.

Saunders' attorney said he plans to file a complaint against King County in civil court for alleged violations of his clients' rights, which led to Saunders being beaten and to pleading guilty.