KCBS reports that dozens of police cars, fire engines and ambulances surrounded and blocked off the area. The radio station reports that the police action came as a surprise.
Protester Katt Hoban says there were several hundred protesters at the encampment of about 200 tents. Hoban reported the raid started around 2 a.m. local time when about 200 riot police surrounded the camp.
KCBS says several tents were taken down and that protesters had been allowed to retrieve their belongings and leave before authorities moved in.
It was not immediately clear whether there had been clashes, injuries or arrests.
Attempts to reach police for comment were not immediately successful.