The arrests were made after hundreds of protesters marched around the streets of Oakland on Monday night.
A waiter, who was guarding windows at a restaurant, was hit in the face when protesters threw fireworks at police, the Associated Press reported.
Thousands of people across the United States took to the streets to continue their protests for the third consecutive day after a Florida court cleared Zimmerman of last year’s killing of unarmed African-American teenager Trayvon Martin.
In Los Angeles, at least 13 people were arrested over violence and vandalism in city streets on Monday.
After the verdict’s announcement, Zimmerman went back into hiding, his parents told ABC News.
According to the Zimmermans, they have remained in hiding too because of “an enormous amount of death threats.”
“We have had an enormous amount of death threats. George’s legal counsel has had death threats, the police chief of Sanford, many people have had death threats,” Robert Zimmerman said.
The neighborhood watchman was charged with second-degree murder for killing Martin in February 2012 in Sanford, Fla. However, the jury was allowed to consider manslaughter.
Zimmerman has claimed that Martin attacked him and he acted in self defense.
Meanwhile, two petitions are calling for Attorney General Eric Holder to file civil rights charges against Zimmerman.
One petition on the “We the People” section of the White House’s website urged the Justice Department to prosecute Zimmerman for “depriving Trayvon Martin of his Constitutional Rights of Life and Liberty.”
The Justice Department said it was evaluating whether it had enough evidence to support Zimmerman’s prosecution in federal court.