MINNEAPOLIS (WCCO) — Four men who Minneapolis police say armed themselves with water guns and then attacked a passing pedal pub appeared in court Thursday.

Witnesses say a group of men attacked a pedal pub with water balloons and squirt guns two weekends ago. Some of the passengers were off-duty Burnsville police officers, who held down the assailants until Minneapolis officers arrived.

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Six men were arrested.

On Thursday, three men pleaded not guilty to charges of disorderly conduct. They were Jason Leonard Carlton, Mark William Dean and Francis Wayne Bellanger. A fourth, Kurtis Wayne Johnson, pleaded not guilty to fifth-degree assault charges.

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John Davis Rock Jr. also faces charges of disorderly conduct and fifth-degree assault, but his arraignment will be on June 22. Charges are still pending against Ryan Michael Paul Barth.

A manager of the Pedal Pub company says they were on alert that night after being notified about a Facebook post that encouraged people to attack the pubs.

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No one was seriously injured in the incident.