Oakland, Calif., Mayor Jean Quan has apologized for a clash between police and protesters during a march against economic inequality that left a former U.S. Marine seriously wounded, and said she would meet with demonstrators.

Quan, who has come under withering criticism for her handling of the protests, said in a written statement that she had met with ex-Marine Scott Olsen and his parents and was concerned about his recovery.

Olsen, 24, was struck in the head during protests in Oakland on Tuesday night and has become a rallying cry for the so-called Occupy Wall Street protests nationwide.

A representative of Highland General Hospital in Oakland said Olsen remained in fair condition on Friday, having been upgraded from critical one day earlier, and was visiting with his parents.

I am deeply saddened about the outcome on Tuesday, Quan said in the statement. It was not what anyone hoped for, ultimately it was my responsibility, and I apologize for what happened.

When there's violence there are no winners, she said. It polarizes us and opens old wounds rather than brings us together, which is the aim of Occupy Wall Street and uniting the 99 percent.

The Occupy Wall Street protests, which began in New York last month, take issue with a financial system protesters say most benefits corporations and the wealthy. They are critical of U.S. government bailouts of big banks, high unemployment, and economic inequality.

Rallying Cry

The 99 percent refers to their rallying cry that the richest 1 percent of Americans control too much of the wealth.

Quan said she and acting Oakland Police Chief Howard Jordan would meet with representatives of the city's protesters, but asked the group not to camp overnight in Frank Ogawa Plaza near city hall.

Police dismantled the encampment in the plaza early Tuesday morning, and protesters were marching to retake it that evening when Olsen was injured.

Protest organizers say the ex-Marine was hit by a tear-gas canister fired by police. City and police officials have not said how they believe Olsen was hurt, but Jordan has opened an investigation into the incident.

On Friday, the Iraq and Aghanistan Veterans of America called for a full and complete investigation into the circumstances surrounding the incident.

The injury of any veteran is a serious concern to the broader veterans community -- especially when it happens on American soil, the group said in a statement on its Web site.

Scott Olsen and his family are in our thoughts and prayers, and we hope for his speedy recovery.

Occupy Oakland organizers have called for a general strike over what they called the brutal and vicious treatment of protesters there, including Olsen.

At the downtown plaza where he was hurt, several hundred supporters turned out Thursday night for a candlelight vigil in which fellow activists from a group called Iraq War Veterans for Peace addressed the crowd.

One drew loud cheers when he said the police chief or mayor should resign.

(Writing by Dan Whitcomb; Editing by Greg McCune and Jerry Norton)