CHICAGO (WLS) -- In the aftermath of 9/11, U.S. law enforcement obtained al Qaeda notes that Chicago was on the original hit list personally put together by Osama Bin Laden. The target then was known as the Sears Tower, according to one captured terror operative questioned by American intelligence.
When terrorists commandeered planes on 9/11, federal investigators say Chicago and Los Angeles were on Al Qaeda's original target list along with the U.S. Capitol and Israel's Embassy in Washington. FBI officials have said fortunately Chicago and the others didn't make Bin Laden's final cut.
The I-Team asked former Deputy U.S. Marshal Ed Farrell if Chicago is still a target in the eyes of foreign terrorists.
"Absolutely," said Farrell.
He was part of a federal task force in Chicago when 9/11 happened. He says Chicago and other big cities have soft targets including schools and stadiums that are attractive to foreign terrorists.
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"They're looking for events with mass casualties to further them. So that's why Chicago is such a priority," said Farrell.
He also says the September 11th date is of special concern.
"September 11 is a very significant day to Islamic history. So, it goes back to 1683 when the King of Poland, took back the Ottoman Empire...and they view September 11 is the end of the 300 year of subjugation to the west," said Farrell. "We've also seen other attacks on September 11, in Benghazi. So, it's an important day."
With Bin Laden dead and his successor al-Zawahiri's status uncertain, the latest Homeland Security/FBI alert says there are no known threats to the U.S. However, "Homeland Violent Extremists who desire to travel to join Foreign Terrorist Organizations but are unable to do so may instead seek to conduct attacks in the United States."
"They use plotters and bomb experts to train people online so that they can carry out attacks here," said Elizabeth Neumann, ABC News Contributor and former DHS Assistant Secretary for Counter Terrorism.
"The threat today is different than what we faced 20 years ago. As we stand here today, 20 years after the 9/11 attacks, we stand stronger and safer as a country," said Department of Homeland Security Secretary Alejandro Mayorkas.
He said that is primarily due to a sharing of intelligence, equipment and personnel between federal, state and local agencies since 9/11. Spanning the years since 2001, some U.S. and city officials discredited reports that Chicago was a 9/11 target. That came to an end in 2010 when former President George W. Bush said the former Sears Tower had indeed been a target.