Two St. Louis men reportedly planned to blow up the city’s iconic Gateway Arch and kill two prominent figures in the Michael Brown shooting case in Ferguson, which has sparked protests nationwide.

The St. Louis Post-Dispatch reported Wednesday that Brandon Orlando Baldwin and Olajuwon Ali Davis were indicted last week on federal weapons charges but authorities expect more charges to be filed against the duo relating to the alleged plot.

According to the newspaper, police sources said it was unclear if the men had the capacity to actually carry out their plan. The two allegedly bought what they believed was a pipe bomb in an undercover operation and had planned to buy more.

The men also allegedly had planned to kill St. Louis County Prosecuting Attorney Robert McCulloch and Ferguson Police Chief Tom Jackson, both officials involved in the Michael Brown shooting case.

The newspaper reported that it was unclear whether the men planned to use the bombs to kill McCulloch and Jackson.

The St. Louis Post-Dispatch reported that the men had wanted to buy more of the “bombs,” but had to wait until one of their girlfriends’ Electronic Benefit Transfer card had more money.

The men were arrested three days before a grand jury declined to indict Ferguson officer Darren Wilson on charges for killing 18-year-old Michael Brown in an August shooting.

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