While two brothers reportedly motivated by Islamic fundamentalism were carrying out the Boston Marathon bombing, the city was hard at work planning a mass casualty terrorism-training exercise in which the perpetrators were American militiamen whose logo includes Uncle Sam hats.

The Boston Globe revealed the plot of “Operation Urban Shield,” a simulation by the Department of Homeland Security costing $200,000. The program was slated to take place last weekend to train local Boston law-enforcement agencies to work together to thwart a terrorist threat.

The Boston newspaper reported officials from a dozen agencies had been meeting for months to plan the simulation and had already recruited students from Northeastern University and the Boston Police Academy to play the parts of terrorists and witnesses.

While the vast majority of all terrorist attacks worldwide are carried out by Muslims, the DHS program decided to train for a different set of antagonists.

According to the plans obtained by the Boston Globe, the terrorist threat in the exercise was a fictional group called the Free America Citizens, described as “a home-grown cadre of militiamen whose logo would be a metal skull wearing an Uncle Sam hat and a furious expression.”

One official told the newspaper the goal of the simulation was for detectives to figure out the motives of the Free America Citizens group.

Now that an eerily similar plot was carried out to deadly effect by the Chechen Muslim brothers Dzhokhar and Tamerlan Tsarnaev, the “Urban Shield” drill is reportedly retooling some of the stimulation.

However, it was unclear whether Islamic ideology would play a part in the future drill.

Transit Police Chief Paul MacMillan, whose agency was slated to participate, told the Boston Globe he anticipates the new training scenario will be similar to the one already planned.

“Why wouldn’t we do it?” MacMillan said. “Just because we had one event doesn’t mean that we might not have another one. And it behooves us to continually work together to investigate these types of incidents.”

“Urban Shield” is described as a 24-hour exercise meant to test the response police and other public agencies public safety personnel in a large-scale emergency.

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