Deputies punched a driver until he was on the ground, then allowed a police dog to bite the man Monday after a high-speed pursuit involving Charleston County Sheriff Al Cannon, according to video acquired Thursday by The Post and Courier.

The video confirms allegations by the family of Timothy Shawn McManus, who was arrested Monday morning following a pursuit that reached speeds of 120 mph, and contradicts some of the accounts initially given by the Charleston County Sheriff’s Office. The sheriff’s office had previously said that a K-9 brought down the 31-year-old McManus as he tried to run away.

Cannon started the chase about 9:45 a.m. Monday when he spotted McManus’ Dodge pickup driving recklessly near Mount Pleasant. Several deputies joined the chase by the time it ended a half hour and 25 miles later.

“At the end of the vehicle chase, he bailed out, and a K-9 caught him and took him out,” Cannon said during a news conference Monday. Cannon also acknowledged during a separate news conference Wednesday that he was angry when he slapped McManus with an open hand as McManus sat restrained in a patrol car.

The State Law Enforcement Division as well as internal affairs investigators from the sheriff’s office are looking into the chase that ended with Cannon and other deputies shooting out the tires of McManus’ pickup.

The video taken from a deputy’s dashboard camera shows a lone deputy pulling McManus out of the truck and starting to punch him. McManus raises his handed above his own head as if to protect himself as other deputies try to restrain him.

He suffers about five blows from closed fists as he goes to the ground, according to the video.

With deputies on top of McManus, a police dog leads another deputy into the picture. The dog is allowed to bite McManus for about 10 seconds, until the deputy starts struggling to remove the dog. The deputy pulls off the dog about 10 seconds later, the video shows.

Sheriff’s Capt. Eric Watson declined to comment on the tactics used in taking McManus into custody.

“That's the reason why it’s an internal investigation as well as a SLED investigation,” Watson said.

McManus is jailed on charges of reckless driving, failure to stop for blue lights and siren, resisting arrest and third-offense driving under suspension.

Victoria Middleton, executive director of the ACLU of South Carolina, applauded the investigations into the incident.

“I don’t want to comment further at this point until we know more about the incident,” she said. “It’s certainly a good thing that the investigation is under way.”