URGENT: Five people described as anarchists were arrested Monday in a Cleveland-area park for trying to blow up a bridge, sources tell Fox News.

The public was never in danger from the explosive devices, which were inoperable and controlled by an undercover FBI employee, according to sources close to the investigation.

Charges were filed against the defendants Tuesday morning in Cleveland. Court documents say three of the suspects are self-proclaimed anarchists who formed a small group and considered a series of plots over several months.

The FBI and the federal Joint Terrorism Task Force are involved in the investigation.

It is unknown if the bridge incident was connected to Occupy Wall Street's plans for nationwide protests Tuesday.

An FBI press conference is planned for 10 a.m.

Fox News' Mike Levine contributed to this report.

Read more: http://www.foxnews.com/us/2012/05/01...#ixzz1tcuRcJb7