A video shot near the intersection of Westlake Avenue and Republican Street in South Lake Union shows Seattle police pepper-spraying protesters, while officers tend to one of their own laying in the street who appears to be injured.

Police have said an officer was assaulted by a protester, who they arrested. The officer was treated for his injuries at Harborview Medical Center and released at 6 p.m. (SPD spokesman Patrick Michaud says the injury was not a broken leg, but didn't have any more information than that.)

At the start of the video, one demonstrator in a black sweatshirt repeatedly advances on the downed officer, and is repelled by other officers pushing him back. They don't arrest or pepper-spray him. As officers on bicycles arrive, the protester disappears off screen.

That's when one officer with a bike starts pepper-spraying, hitting several individuals standing in the street from a few feet away. One man who appears to get a thick faceful begins slowly backing away, trying to shield his eyes. Officers can be heard yelling, "Move back!"

He keeps edging toward the sidewalk, putting his hand out as if unable to see. One officer evetually puts his bike down and grabs him out of the street, which by then had been largely cleared. Police push him to the ground, apparently arresting him.

The person shooting the video comments, "That doesn't seem very necessary."

The Hillman report, commissioned by SPD after May Day 2012, recommended that pepper spray "shall not be used to gain compliance of a passive-resistant protester."

If this is the man they charged with assault, the available video of the incident seems to show the opposite: police assaulting him.

I've asked the man who uploaded the video and SPD for comment. Neither has gotten back to me yet.

UPDATE: SPD's policy manual states that police may use pepper spray during "violent activity" in the context of a demonstration if they have at least one of three primary objectives: "Defend oneself; Defend someone else; Prevent significant destruction of property." The policy says officers must issue warnings before pepper spraying and that each individual spray must be justified. Under former Mayor Mike McGinn, the 20/20 police reform plan called for pepper spray to used "only as a self defense tool."

UPDATE 4 p.m.: SPD spokesman Patrick Michaud says the officer on the ground is the one who was assaulted. The officer, whose name he wouldn't release, was pushed to the ground and suffered a sprained knee or ankle in the course of the fall, Michaud said, and the person who pushed him waved an umbrella or a stick at him.

The Seattle Fire Department won't come into the area to provide treatment until it's "safe and secure," Michaud explained. "If people are getting inside of our line, they will not come in to help us. We have to clear that, to get him the aid that he needs."

Police used pepper spray because up until that point, protesters weren't quickly clearing the area, according to Michaud. "It was pretty effective, from the [looks of] video," he said.

"That one straggler who's caught out in the road," Michaud continued, "looks like he caught a faceful... But when you fail to get out of the road and officers have given you the order to disperse, that's a legal lawful order that you have abide by."

The man who was pepper-sprayed and arrested was charged with failure to disperse. The man who pushed the officer was arrested later on and charged with assault, Michaud said.