Updated

Audio recordings of 911 calls made during the Wisconsin State Fair indicate that some of the violence allegedly perpetrated by so-called "flash mobs" may have been racially motivated, Fox 6 reports.

Thirty people were arrested on Aug. 4 when mob attacks erupted at the fair on opening night. At least 18 people were injured in or around the grounds, including seven police officers.

Authorities have since been investigating allegations of race-based assaults near the state fairgrounds in which the alleged perpetrators were all African-American and the victims were either white or Hispanic.

Fox 6 reports that the Milwaukee County Sheriff's Department released audio of 911 calls made from the fair that graphically detail the nature of the attacks.

One caller told dispatchers, "A whole bunch of black dudes f----- jumped on me. I'm bleeding all over," according to the station.

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Milwaukee Police Chief Ed Flynn has called the attacks "reprehensible," and some fairgoers said it appeared bystanders were targeted because of their race.

The alleged attacks at the Wisconsin State Fair are part of a string of "flash mob"-generated violence around the country -- including cities like Philadelphia and Chicago -- in which packs of dozens or even hundreds of youths appear seemingly out of nowhere to commit assaults, robberies and other crimes against innocent bystanders.

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