Tampa, Florida -- Thirteen years after the 9/11 attacks, we are now learning of allegations of a major FBI cover-up that connects Sarasota and the 9/11 hijackers to the Saudi Arabian government. As 10 Investigates discovered, there is a growing chorus calling for the reopening of the 9/11 investigation and it is being led by one of Florida's most influential leaders: former Senator Bob Graham.

While still at Sarasota's Emma E. Booker Elementary on the day of the 2001 terrorist attacks, President George W. Bush said, "Terrorism against our nation will not stand."

However, the president's visit wasn't the only thing to tie this Bay area county to the September 11th attacks. Within days, we learned three of the hijackers had been living in the area while taking flying lessons at Huffman Aviation and Florida Flight Training in Sarasota County... but there is even more than that.

"There was a network supporting the hijackers," says former U.S. Senator and Florida governor Bob Graham.

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According to Graham, the FBI has been covering up that fact for years, and continues to try and hide it even now. Graham says he is convinced there was a direct line between some of the terrorists who carried out the September 11th attacks and the government of Saudi Arabia.

Graham says the U.S. government doesn't want the American public to find out the Saudis financed the attack, because we provide billions in military aid to Saudi Arabia.

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"That would certainly change our attitude toward arming Saudi Arabia," Graham says.

According to Graham, the FBI was aware of the strong connection between hijackers and a Saudi Arabian family who were living in an upscale Sarasota gated community. Twelve days before 9/11, the family abandoned the house -- leaving behind valuable items including food, clothing, furnishings and three vehicles.

"There are some things I can't talk about," Graham told us, "And there are others like what I know is involved in the investigation in Sarasota, which is diametrically opposed to what the FBI said publicly."

As proof, Graham points to 12 pages of newly declassified documents tying the Sarasota family to the 9/11 hijackers.

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The FBI claims it turned over all of its 9/11 files to the Congressional Committee. But Graham -- who also headed the Congressional Committee Investigation into 9/11 --says he asked other commission members who confirmed they did not receive any documents from the FBI concerning the Sarasota investigation.

There are actually thousands of documents that are not being released.

"After having said there were 'no' documents about the investigation in Sarasota, 'no' has now become 80,000 pages." Graham adds,"I think that should be stunning to the American people, that an agency of our government would deceive its own people so dramatically."

Graham, who is concerned about the ties between ISIS and support groups, points to the new documents that show the Tampa division of the FBI identified an "international businessman" who was a relative of the family and an "antagonist of the United States" and traveled to Sarasota after 9/11 with the intentions, it says, "to begin offensive operations against the United States."

According to Graham, "I am concerned if there was a network assisting the 19 hijackers in place in 2000 and 2001... there is no reason to believe that it was eliminated."

Graham is also irked that there was another post-9/11 incident near Sarasota that caused concern, but the FBI didn't reveal that and we're only learning about it now, since these new documents have been released.

The Tampa Division of the FBI was aware of a man visiting Florida from Tunisia who went to a dumpster in Bradenton to dispose of several items including:

  • A manual on terrorism and Jihad.
  • Flight training information from the flight school the 9/11 hijackers trained at.
  • A map of an unnamed airport.
  • Printed maps of Publix shopping centers in Tampa Bay

But the FBI never informed Congress, despite tell them it released "all the documentation pertaining to the 9/11 investigation."

Graham says he has checked with other members of his committee and the staff, and they all agree the committee was not given anything about the Sarasota connection.

And Graham says the FBI -- which is fighting the release of thousands of pages of its investigation -- is continuing to cover up the Saudi Arabian connection between Sarasota and the 9/11 attack.

"After having said there were 'no' documents about the investigation in Sarasota, 'no' has now become 80,000 pages," Graham says.

After the information about the 80,000 pages came to light, Graham went to the FBI and asked how the agency could lie to Congress. He says the number two man at the agency told him to come back in a week and the FBI would provide all the documents it had previously said didn't exist.

But when Graham came back a week later, he says he was told by the same man that the agency wasn't going to let him see anything or talk to anyone in the FBI.

That leads Graham to ask, "Why has the federal government, including some of its most prestigious agencies, gone to such lengths to cover up what they know?"

Graham believes the reason for the cover-up can be found in 28 pages of the Congressional Investigation into 9/11 -- which Graham helped write -- that remain classified to this day. According to Graham, the 28 pages show an even stronger connection to Saudi Arabia's involvement that the U.S. government wants to hide from the public.

"This is the most confounding, troubling, disturbing thing," Graham says. "This is one of the few things I have trouble going to sleep at night."

Graham and a growing group in Congress are concerned that the United States is vulnerable to another terrorist attack, and he says the American public needs to know the truth.

"I am not the Lone Ranger on this. In fact, the people who know the most about it are the ones who have the most trouble sleeping."

Graham says the more you know, the worse it gets and that if the Broward Bulldog -- a non-profit news service -- hadn't won a Freedom of Information lawsuit, the latest documents would still be withheld from the American public.

Graham is also joining the families of the victims and a growing chorus in Congress pushing to declassify the 28 pages he helped write, release the 80,000 pages and reopen the 9/11 Investigations.