As the Nato summit is in progress in Chicago, protesters are constantly marching to the venue leading to arrests and stray incidents of violence.
Up to 45 protesters have been detained so far and dozens have been injured during the protests.
"I know that picture [of officers in riot gear pushing and hitting protesters] is going to be what people are going to run away here with. But cops are not here to be assaulted," Reuters quoted Chicago Police Chief Garry McCarthy as saying.
Although this is one of the largest demonstrations in Chicago in recent years, the number of protesters who have turned up falls far short of expectations. The protesters are part of the Coalition Against Nato-G8 group.
Thousands of demonstrators flooded the city against the Afghan war, climate change and several other grievances.
Having too many grievances under the same protest quite often dilutes the demonstration, some of them feel.
"It's crazy. There's so many people here. Having Nato in town is kind of exciting. It seems like there is so many messages people aren't really sure what they want to get accomplished. People just need to figure out what their argument is going to be," said Esther Westlake, a recent graduate, reported the Associated Press.
Some of the angry protesters were determined to take on the police. "This is what police brutally looks like. All we're trying to do is protest and the police are attacking us," said an angry young Ryan Zielinski who was hit by a baton as the police tried to push back the protestors, reported Reuters.
It was next to impossible for the protesters to see the world leaders since the meeting venue was guarded by high security and strong fences. The demonstrators were blocked by the police far away from the leaders.