Officials declared the 3-week-old event an unlawful assembly, giving police the green light to clear the campers.
The operation began at about 2:30 a.m. and lasted roughly 45 minutes. Once the protesters were removed, a cleaning crew moved in.
Police said there had been numerous complaints about unsanitary conditions created by human and animal feces, urination, drug use and littering, as well as damage to city property.
Demonstrators began arriving at the plaza on Oct. 7 to protest perceived economic injustice and poverty.
The Associated Press contributed to this story.