SAN FRANCISCO (CBS SF) — A large group of Occupy SF protesters who were demonstrating in front of the Federal Reserve building on Market Street Thursday evening have returned to Justin Herman Plaza to “solidify the camp,” according to a protester.

Two people were arrested Thursday evening during the demonstration, according to police Sgt. Mike Andraychak.

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Police erected barricades at Justin Herman Plaza Thursday after officers and city officials did a walk-through of the camp, Andraychak said.

According to Andraychak, during the walk-through officers found wooden stakes that had been sharpened on both ends and were believed to be potential weapons.

KCBS’ Chris Filippi Reports:

The barricades “were set up to define the perimeter of the camp,” Andraychak said.

But protesters did not see it that way, protester Derk Pippin said.

Pippin said that while protesters are trying to negotiate with police about a possible relocation to the city’s Mission District, the erection of barricades indicates that the city may not be acting in good faith.

“They barricaded us in without telling us why,” Pippin said. “What we saw tonight is a huge reaction to mixed signals.”

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Andraychak said that when the barricades were erected some people packed up and left while others reacted violently.

One officer suffered an injury to his hand, Andraychak said.

Police arrested a man who was kneeling and holding what was later determined to be a laser.

Andraychak said the man was crouched down and aiming the laser at officers in such a way that they believed the man was armed.

The man was arrested and found to be in possession of a knife, Andraychak said.

Around 6:45 p.m. a large group of protesters moved to 101 Market Street, blocking the street to traffic for about an hour.

Andraychak said some protesters attempted to drag police barricades into the street leading to confrontations with police.

The barricades were ultimately removed by police so they could not be used as a weapon or to block the street, he said.

A man was arrested at that time for trying to hit an officer, according to Andraychak.

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