CHICAGO (CBS) — A man who attempted to plant a bomb near Wrigley Field pleaded guilty on Monday and will face 20 to 30 years in prison.

The sentence for Sami Hassoun will be announced in court on Aug. 15.

He pleaded guilty to attempted use of a weapon of mass destruction and attempted use of an explosive device.

Hassoun, was accused of placing a backpack he thought contained a bomb near Wrigley Field in September 2010 on the night of a Dave Matthews Band concert. He originally pleaded not guilty.

Hassoun was accused of plotting to place a bomb in a trash can outside Sluggers Sports Bar in the 3500 block of North Clark Street in Wrigleyville, to create a massive explosion.

The purported bomb was actually an inert device that was provided by undercover FBI agents, who were investigating and monitoring Hassoun’s proclaimed determination to commit acts of violence in Chicago, according to a release from the U.S. Attorney’s Office in Chicago.

LISTEN: WBBM Newsradio’s Regine Schlesinger Reports

As a result of the undercover investigation, Hassoun never posed any actual imminent danger, but his plea agreement makes clear that he intended to cause mass casualties and had rejected opportunities to walk away from the plot, prosecutors said.

Hassoun, 24, formerly of the city’s North Side, remains in federal custody while awaiting sentencing. Hassoun is a Lebanese citizen and permanent resident alien.

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