UPDATED 05/21/12 – 6:14 p.m.

CHICAGO (CBS) — As NATO officials were wrapping up their summit in Chicago, anti-NATO protesters marched to Boeing headquarters Monday morning before turning their attention to President Obama’s campaign headquarters on the other side of the Loop.

As CBS 2’s Marissa Bailey reports, the demonstrators were protesting the company’s involvement in building aircraft and missiles for the U.S. military. The protesters say Boeing is a “war machine that produces war machines.”

LISTEN: WBBM Newsradio’s Steve Miller reports

The protest began at 9 a.m. at Union Park, at Ashland Avenue and Lake Street on the Near West Side. Around 10:45 a.m., a group of about 100 protesters began marching toward Boeing headquarters.

The protesters arrived at the south end of the building, at Washington Street and the Chicago River, around 11:20 a.m., and many of them laid down in the street, in a “die-in” against Boeing.

One onlooker said of the protest group, “my family reunions are bigger than this.”

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Protesters marched from Boeing Headquarters east on Washington Street and staged a sit-in near the County Building at Washington and Clark. (Credit: John Dodge/CBS Chicago

CBS 2’s Dorothy Tucker reports protesters chanted, “What do we want? Peace! When do we want it? Yesterday!” as they parked themselves in the middle of the street, blasting the company’s profits from making warplanes and missiles.

As speakers railed against the company’s products – which include unmanned spy drones – protesters made paper airplanes, which they said symbolize the peaceful world they’re trying to foster.

“Take those billions of dollars and put it into people’s needs for life, not killing people around the world,” one protester shouted through a bullhorn.

“I would definitely say Boeing has blood on its hands. You know, they get a lot of tax breaks from us, and on a personal level, I hate to see it going towards the war machine that is NATO,” Occupy Chicago demonstrator Blaise Suwell said.

When Boeing moved its headquarters to Chicago in 2001, it received about $53 million in tax incentives and grants from the city and state.

A company spokesman said he thinks it is unfortunate that many protesters think Boeing creates war machines.

“We wish and hope that people understand what we do. We understand that they are upset with us for whatever reason. Having said that, to the extent that we have a role in protecting our troops – protecting the people who are protecting all of us – that’s something we’re proud of and our employees are proud of,” said spokesman John Dern.

Last week, Boeing covered its street-level windows with aluminum panels in preparation for possible vandalism during the protest. Protesters call that move a victory, saying they have successfully shut down Boeing headquarters – at least for a day.

The anti-NATO protesters say they did not consider Monday’s march a protest, but rather a celebration, as they were hoping to shut down Boeing — which had most its employees work from home. But Boeing insisted its headquarters was open for business, although only a handful of workers was working downtown, with most of the headquarters’ staff working from home.

The rally outside Boeing was one of the smallest groups of protesters to date, yet police were just as vigilant; even admitting – like at every other march – police, federal agents, and other law enforcement officers were posing as protesters.

“We’ve had a large undercover component working throughout this event and it’s been very helpful,” Police Supt. Garry McCarthy said.

Demonstrators were convinced they spotted one of the undercover officers on Monday. In the background, several protesters were heard describing a man in a blue hoodie and blue bandana.

“You can see his gun on his belt,” one protester said.

As that man began to back away from the crowd, demonstrators began booing him.

There was more booing for police when a protester was arrested later. As officers led the man away, a police commander described his alleged crime.

“He was spray painting and he’s got fireworks on him,” the commander said.

Police said the man was spray painting a sign near the crowd. What the man might not have known, if he was from out of town, is that spray paint and fireworks are illegal to possess in Chicago.

Around 12:15 p.m., protesters began marching east on Washington Street again, then wound their way through the Loop to Michigan Avenue and Monroe Street, before heading north to go to Prudential Plaza, and President Barack Obama’s campaign headquarters. The group gradually grew larger as they made their way through the Loop, eventually growing as large as 250 to 300 people.

“Boeing is the war machine. Barack Obama is the war maker. So we’re taking this from the supplier to the buyer,” one protester said while marching to Obama campaign headquarters.

As of 1:20 p.m., the marchers had stopped at Washington Street and Michigan Avenue, and were staging a sit-in in the northbound lanes of Michigan Avenue. Several hundred protesters gathered for what WBBM Newsradio’s Steve Miller called a “Kumbaya-type rally” rather than anything with the potential for violence.

nato protest boeing may 21 Anti NATO Group Rallies Outside Boeing, Obama Campaign HQ

Protesters marched from Boeing Headquarters east on Washington Street and staged a sit-in near the County Building at Washington and Clark. (Credit: John Dodge/CBS Chicago

By 1:30 p.m., protesters had proceeded east Randolph Street from Michigan Avenue, and came to a stop at the Prudential Plaza where Obama’s campaign headquarters are located, WBBM Newsradio’s Nancy Harty reported. Randolph Street was closed near the scene.

Members of the group were making speeches that they are upset with President Barack Obama and believe they betrayed him.

CBS 2’s Mike Puccinelli reports a representative of lawyers group also decried what she called acts of police brutality during Sunday’s much larger protest march and rally outside the NATO Summit at McCormick Place.

“We have almost 60 accounts of police brutality, mainly from just from last night,” said Sarah Gelsomino, with the National Lawyers Guild, which is representing protesters who have been arrested over the past week, as well as several men arrested in separate alleged bomb-making plots.

Despite having no pre-set route for their march through downtown, and not having announced publicly in advance that they’d be going to Obama campaign headquarters after the protest at Boeing, interactions between protesters and police were peaceful, for the most part.

“We have an unscheduled, unpermitted protest, and we’re doing exactly as we said. We’re facilitating protesters, keeping them safe and helping them express their first amendment right to free speech,” McCarthy said.

In the week leading up to the NATO summit, Occupy Chicago has held several demonstrations to protest the organization. McCarthy said covering the cost of extra officers on duty and overtime won’t be coming from the city.

“That money was raised and funded outside the budget of the city. The mayor made a promise that the taxpayers of the city would not have to foot the bill for this, and he stayed true to that word,” he said.

At least two uniformed Chicago Police officers were videotaping the demonstration. A protester wielding a cell phone camera took issue with the officer recording him, and the protester and officer ended up confronting each other lens to lens, Harty reported.

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