Footage from Toronto hearings 10 years after 9/11, as scientists give their theories on the terrorist attacks that occurred on Sept. 11, 2001.

Over four days of hearings, scientists provide their perspectives on how the terrorist attacks unfolded on Sept. 11, 2001.

On the 10-year anniversary of the 9/11 attacks, scientists gather for the four-day Toronto Hearings; they have their own theories about what occurred on that day, some of which go far beyond accepted truths.

Scientists gather for the Toronto Hearings a decade after the events of Sept. 11, 2001, to present their theories on what truly occurred that day.

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