Most of the raids concerned politically motivated right-wing incitement, according to the Federal Criminal Police Office, whose officers conducted home searches and interrogations.
But the raids also targeted two people accused of left-wing extremist content, as well as one person accused of making threats or harassment based on someone’s sexual orientation.
“The still high incidence of punishable hate posting shows a need for police action,” Holger Münch, president of the Federal Criminal Police Office, said in a statement.
“Our free society must not allow a climate of fear, threat, criminal violence and violence either on the street or on the internet.”
The raids come as Germans are debating the draft of a new social media law aimed at cracking down on hate speech, a measure that an array of experts said was unconstitutional at a parliamentary hearing on Monday.