Published: Oct 27, 2011 11:12 PM EDT

OAKLAND, Calif. (AP) - The Iraq War veteran injured during a clash between police and anti-Wall Street protesters wasn't taking part in the demonstrations out of economic want.
    
Scott Olsen, 24, makes a good living as a network engineer and has a nice hillside apartment overlooking San Francisco Bay. And yet, his friends say, he felt so strongly about economic inequality in the country that he fought for that he slept at a San Francisco protest camp after work.
    
"He felt you shouldn't wait until something is affecting you to get out and do something about it," said friend and roommate Keith Shannon, who served with Olsen in Iraq.
    
It was that feeling that drew him to Oakland on Tuesday night, when the clashes broke out and Olsen was struck by a projectile that fractured his skull.
    
Now, even as officials investigate exactly where the projectile came from, and from whom, Olsen has become a rallying cry for the Occupy Wall Street demonstrators across the nation, with Twitter users and protest websites declaring: "We are all Scott Olsen."
    
In Las Vegas, a few dozen protesters held a vigil Wednesday night, carrying glow sticks and projecting a photo of the Marine in uniform onto the corrugated-metal side of building at their camp.
    
More vigils were being planned Thursday night in other cities.
    
Elsewhere, officials took steps to close some camps that sprang up since the movement began last month against what protesters see as corporate greed and a government that caters to the wealthiest and big business.
    
In Nashville, Tenn., officials imposed a curfew for a camp at the Capitol complex. In Providence, R.I., officials notified protesters that they were violating laws prohibiting camping overnight at a park.
    
On Thursday, however, much of the talk was of Olsen and who was responsible for his injury.
    
The group Iraq Veterans Against the War blamed police. Oakland police Chief Howard Jordan said officials will investigate whether officers used excessive force.
    
Olsen's condition improved on Thursday, with doctors transferring him from the emergency room to an intensive care unit. His parents were flying to Oakland from Wisconsin, his uncle said.
    
"His mother, this is obviously a heartbreaker to her," said George Nygaard, also a Marine veteran, said. "I don't think she understands why he was doing this."
    
Olsen, who is from Onalaska, Wis., served two tours in Iraq, felt the anti-Wall Street movement had a chance to create real change, Shannon said. So each night, he would go out to the tent camps and usually called Shannon with his whereabouts.
    
On Tuesday night, Olsen had planned to be in San Francisco, but changed course after his veteran's group decided to go to Oakland to support the protesters there. Earlier, police in riot gear cleared an encampment outside city hall that officials said had health and safety problems.
    
"I think it was a last minute thing," he said about Olsen's decision. "He didn't think about it."
    
Joshua Shepherd, 27, a Navy veteran who was standing nearby when Olsen got struck, said he didn't know what hit him. "It was like a war zone," he said.
    
Then there was a scramble and he couldn't clearly see the rush of folks who went to Olsen's aid.
    
A video posted on YouTube showed Olsen being carried by other protesters through the tear gas, his face bloodied. People shout at him: "What's your name? What's your name?" Olsen, however, just stares back.
    
Shepherd said it's a cruel irony that Olsen is fighting for his life in the country that he fought to protect. "He was over there protecting the rights and freedoms of America and he comes home, exercises his "freedoms" and, it's here, where he's nearly fatally wounded," Shepherd said.
    
People at OPSWAT, the San Francisco security software company where Olsen works, were devastated after learning of his injuries. They described him as a humble, quiet guy who worked hard over long hours.
    
"He's been a big piece of what we do here and our growth strategy, so obviously it's pretty devastating for us that he's in the shape he's in," said Jeff Garon, the company's director of marketing.
    
Olsen had been helping to develop security applications for U.S. defense agencies, building on expertise gained while on active duty in Iraq, Garon said.
    
Olsen was awarded seven medals while serving in the U.S. Marine Corps, which he left as a lance corporal in November 2009 after serving for four years. One of them was the Navy-Marine Corps Achievement Medal.
    
Olsen moved to the Bay Area in July, and quickly found friends in the veterans against the war group. The lanky man with a dry sense of humor did not show a lot of interest in politics as a teen - he has two tattoos for the group "Insane Clown Posse" on his upper arms, Shannon said.
    
His tours of duty in Iraq made him more serious, Shannon said.
    
"He wasn't active in politics before he went in the military, but he became active once he was out  ... the experience in the military definitely shaped him," Shannon said.

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