OAKLAND (CBS 5) – A U.S. Marine who had served two tours of duty in Iraq was critically injured during an altercation between police and protesters on the streets of Oakland Tuesday night.

Scott Olsen sustained a skull fracture after being shot in the head with a police projectile, according to a press release from Iraq Veterans Against the War – which claims Olsen as a member.

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Friends told CBS 5 that the injury was a skull fracture, and Oakland’s Highland Hospital spokesperson Curt Olsen confirmed that Scott Olsen’s condition was listed as critical.

The protests began around 4 p.m. near the main branch of the Oakland Public Library at 14th and Madison streets. The crowd was ordered to disperse several times as they marched from the library to City Hall.

During the protests Tuesday night many officers were assaulted, doused and hit with hazardous materials and hit with large rocks and bottles, police spokeswoman Cynthia Perkins said. Perkins said this resulted in a declaration of an unlawful assembly. To enforce dispersal orders officers used less-than-lethal force tactics.

Photo Gallery: Occupy Oakland Protests

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The rallies followed 79 arrests made Tuesday morning at the Occupy Oakland encampment at Frank Ogawa Plaza.

Scott joined the Marines in 2006, served two-tours in Iraq, and was discharged in 2010. Scott moved to California from Wisconsin and currently works as a systems network administrator in Daly City, according to the press release.

Scott was sedated at a local hospital awaiting examination by a neurosurgeon Tuesday, according to Iraq Veterans Against the War.

The “Occupy Oakland” demonstrators announced Wednesday that they planned to return to the plaza every night at 6 p.m. to continue the protest in support of the Occupy Wall Street movement.

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