Last Updated 1:51 p.m. ET
(CBS/AP) CHICAGO - Chicago braced for more demonstrations Monday, with protesters marching to Boeing Corp. headquarters, a day after police clashed with a group of demonstrators at the end of a march protesting the NATO Summit.
CBS Station WBBM correspondent Marissa Bailey reports the demonstration outside Boeing's headquarters on N. Riverside Plaza in the West Loop will protest the defense contractor building aircraft and missiles for the U.S. military.
The protesters say Boeing is a "war machine that produces war machines."
So far there have been no arrests at Monday's protests according to Police Superintendent Garry McCarthy.
At about 11:00 a.m. CT protesters left Union Park and began walking along Lake Street toward Boeing, about 1.5 miles away, chanting, "We're going to beat back the Boeing attack."
Police are walking their bikes in ahead of them.
Last week Boeing covered its street-level windows with aluminum panels in preparation for possible vandalism during the protest. The Associated Press reported city workers unloaded metal barricades and placed them in front of Boeing's headquarters Monday morning. Guards outside the building include at least one dog handler with a K-9.
Two activists have hung up a sign on a metal fence outside Boeing headquarters reading, "Food not bombs."
The group does not have a permit for the protest, and thus, a large police presence is expected. However, demonstrators are not calling the planned event a protest at all, said Bailey. They are calling it a victory party, complete with food, clowns, music and dancing.
Many downtown businesses have told their employees to stay home during the second and final day of the summit where world leaders are discussing the war in Afghanistan, European missile defense and other security issues because of traffic snarls and the possibility of more protests.
More than two dozen Metra rail stations along a line that carries around 14,000 riders in from the southern suburbs on most weekdays will be closed, and stations and platforms patrolled by a larger contingent of law enforcement personnel and K-9 units. The Chicago Transit Authority will have to reroute 24 buses through the summit zone.
On Sunday, several thousand protesters marched through downtown in one of Chicago's largest demonstrations in years, airing grievances about war, climate change and a wide range of other complaints as world leaders assembled for a NATO summit.
Although the march was largely peaceful, late Sunday police and demonstrators clashed. Police Superintendent Garry McCarthy said 45 protesters were arrested.
Four officers suffered minor injuries Sunday, the U.S. Secret Service told WBBM. A spokesperson with Mercy Hospital said seven protesters were treated and released.
Some protesters claimed (via Facebook and Twitter) that police officers attacked peaceful demonstrators without provocation, reports WBBM. But one police blog countered that an officer was attacked with a clawhammer.
Beginning late Sunday night a few dozen protesters held a vigil outside the police station on Belmont Ave., waiting for others to be released from jail - and cheering as those who had been detained emerged one by one. Some protesters flew an American flag upside-down as a symbol of protest, reports WBBM correspondent Susanna Song.
Officers outside the police station watched the protesters in case the situation got out of hand.
One woman who had been released from jail told reporters she had been charged with "refusal to disperse, I think . . . It wasn't really that serious."
Occupy Chicago member Bobby Hines of Chicago was arrested on charges of reckless conduct. He claimed that police officers attacked non-confrontational protesters during the march Sunday.
"It was ridiculous - I mean, just right as we were walking, they started hitting people with their billy clubs. I saw people with their eyes gashed out," Hines said. "It was basically a misuse of power in my opinion."
Organizers with the Occupy Chicago movement planned to gather at a West Side park at 9 a.m., and an hour later march toward the Boeing building along the Chicago River in the city's business district to protest the company's role in building aircraft for the U.S. military.
Later, immigration rights activists will gather at the same park before boarding a bus to travel to the small village of Crete, about 35 miles south of Chicago, where federal officials are considering building a nearly 800-bed detention facility for illegal immigrants slated for deportation.
Andy Thayer, one of the main anti-NATO protest organizers, said he expected many demonstrators from out of town to leave Sunday night. But he said a strong contingent of protesters still will show up for the Boeing protest Monday morning.
He decried how city leaders and police officials have handled the protests. "I am disgusted, particularly, with the upper echelon of our city," Thayer said.
Sunday's protests drew together a broad assortment of participants, including peace activists joining with war veterans and people focused on economic inequality. But the diversity of opinions also sowed doubts about whether there were too many messages to be effective.
The protests lacked the size and singular message that shaped the last major protest moment in Chicago, when nearly half a million people filled the city's downtown in 2006 to protest making it a felony to be an illegal immigrant.
And some of the most enduring images of the event were likely to be from the end when a small group of demonstrators clashed with a thick line of police who tried to keep them from the lakeside convention center where President Obama is hosting the gathering of world leaders.
The protesters tried to move east toward McCormick Place, with some hurling sticks and bottles at police. Officers responded by swinging their batons. After nearly two hours, the two sides were still locked in a standoff, with police blocking the protesters' path and the crowd refusing to leave. Some protesters appeared to have blood streaming down their faces.
Following the main skirmish, Police Superintendent Garry McCarthy said 45 protesters were arrested. Police said four officers were hurt, including one stabbed in the leg. Those numbers seemed certain to rise, as new clashes erupted later.
Hundreds of protesters gathered late Sunday night near the Art Institute of Chicago as first lady Michelle Obama hosted a dinner inside for spouses of NATO leaders. At least 100 Chicago police officers in riot gear were also at the scene.
The group of several hundred tried to send a message to the spouses of NATO leaders attending the event inside, sitting in the middle of Michigan Avenue in a driving rain chanting, "Our Streets, Our Streets." The group started dancing as the rain fell.