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9/11: A new book asserts that Iran and Saudi Arabia were involved in the attacks, in which nearly 3,000 people lost their lives
As the 10th anniversary of 9/11 approaches, two authors who've analysed thousands of documents relating to the attack conclude that both Iran and Saudi Arabia helped Al-Qaeda carry it out.

In the aftermath, both countries publicly stated that they'd fight terrorism and expressed their condolences, but The Eleventh Day, by Anthony Summers and Robbyn Swan, produces a compelling argument that they were actually complicit in the attacks.

The book also questions whether George W Bush deliberately withheld evidence linking foreign countries with the attack on the Twin Towers.

The official U.S investigation into the attacks - the 9/11 Commission - found no evidence that Iran was involved, but Summers and Swan beg to differ.

They point to a court document called the Havlish memorandum, which was produced during a civil action brought against Iran by Fiona Havlish, the widow of an insurance consultant who worked in the World Trade Center and was killed when the planes struck.

In seeking compensation from the state it drew on the testimony of several experts, including a French investigative magistrate, former CIA agents, an Israeli intelligence analyst and former 9/11 Commission staff members.

It also includes evidence from three Iranian defectors.

The memorandum states that Hizbollah, the paramilitary group supported by Iran, knew 9/11 was going to take place.

It asserts that one of its key members, Iman Mughniyah, met with Osama Bin Laden and his No2, Ayman Al Zawahiri as long ago as 1993 and also travelled with members of the 9/11 hijackers on flights to and from Iran in 2000.

It's claimed he also went to Beirut with hijacker Ahmed Al Ghamdi and 'visited Saudi Arabia to coordinate activities there' and that two of the terrorists, Khalid al-Mihdhar and Nawaf al-Hazmi, were put up in the Iranian embassy during a visit to Malaysia.

The document also states that Al-Qaeda operatives have received airline hijacking training in Iran.

Evidence linking Saudi Arabia to 9/11 is even stronger, according to the authors.

To begin with, they point out, 95 per cent of Saudi professionals polled about 9/11 stated that they agreed with Bin Laden's cause.

Bin Laden, who was born into a wealthy Saudi family, was publicly denounced by the government and had his citizenship removed, but Summers and Swan quote a former French intelligence officer, Alain Chouet, who says that this was 'a subterfuge aimed at the gullible, designed to cover a continuing clandestine relationship'.

They go on to claim, sourcing a U.S official, that two Saudi princes paid bin Laden 'protection money' - in return for Al-Qaeda not carrying out operations in Saudi Arabia, the authorities would turn a blind eye to his operations elsewhere.

FBI counter-terrorism chief John O'Neill, speaking before 9/11, summed it up. He's quoted in the book as saying that 'all the answers, all the clues that would enable us to dismantle Osama bin Laden's organisation' were in Saudi Arabia.

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The authors unearthed more evidence in the form of a shady Saudi operative called Omar al-Bayoumi, who was alleged to have met two of the hijackers in Los Angeles.

There's also the fact, they say, that 13 of the 19 hijackers were from Saudi Arabia and that U.S investigators working on the 9/11 inquiry complained of Saudi officials continually blocking requests for information.

And why, they ask, was a Saudi religious official staying at the same Marriott hotel as two of the hijackers the night before 9/11?

The authors also place a huge question mark over George W Bush's actions after 9/11. They say that 28 pages of the report of Congress's Joint Inquiry into 9/11 were withheld from the public 'on the personal orders of George W Bush'.

An explanation for this, they say, came from the inquiry's staff director, Eleanor Hill.

She said: 'It had to do with sources of foreign support for the hijackers.'

This information, they point out, is still being withheld.