While the Sept. 11 commission found that contacts between Al Qaeda (search) and Iraq existed in the past, it also pointed to another country with potential ties to the terror network: Iran.

The report released Thursday by the National Commission on Terrorist Attacks Upon the United States (search) says that detained terrorists, possibly including Al Qaeda operational planners Khalid Shaikh Mohammed and Ramzi Binalshibh, confirmed that several of the Sept. 11 hijackers traveled through Iran en route to or from Afghanistan.

At least eight of the hijackers took advantage of the Iranian practice of not stamping Saudi passports, the captured terror suspects allegedly said. They denied any other reason for the hijackers' travel through Iran.

In his State of the Union address in January 2002, President Bush (search) included Iran — along with Iraq and North Korea — in the so-called "axis of evil."

Former Iranian President Hashemi Rafsanjani said Friday that it was not certain that the hijackers passed through his country.

"Every day, thousands of people come and go. ... Such people usually carry false passports. Moreover, many can illegally cross the border. It has been always like this," Rafsanjani said in a sermon. "Even if it's true that they have passed through Iran, can you really incriminate Iran with this bit of information?"

Binalshibh is a suspected coordinator of the Sept 11. attacks on the United States and has acknowledged meeting with Mohamed Atta (search), the leader of the hijackers and pilot of one of the commercial jetliners that demolished the World Trade Center's twin towers. Binalshibh and Atta, an Egyptian, met in July 2001.

Shaikh Mohammed reportedly was the head of Usama bin Laden's terror operations and was the mastermind of the Sept. 11 attacks, the 1998 U.S. embassy bombings in Kenya, the Bali nightclub bombings, the murder of Wall Street Journal reporter Daniel Pearl and other Al Qaeda attacks.

The two captured terrorists denied any relationship between the hijackers and Lebanese Hezbollah, the Iranian-sponsored Shiite militant organization that is on the U.S. State Department list of terrorist groups, according to the Sept. 11 commission's report.

'We Know of a Relationship'

There is strong evidence that Iran facilitated the transit of Al Qaeda members into and out of Afghanistan before Sept. 11; some were future 9/11 hijackers, the report concluded.

There is also circumstantial evidence that senior Lebanese Hezbollah operatives were closely tracking the travel of some of the hijackers into Iran in November 2000.

"We know of that kind of collaboration," commission co-chairman Thomas Kean, a former Republican governor of New Jersey, said of the Iran-Al Qaeda relationship Thursday. But he said there's "no evidence whatsoever" that either Iran or Lebanese Hezbollah knew the specifics of the attacks or helped further plans for them.

"We know of a relationship; how deep that relationship is ... that's going to require more research," Kean said.

The panel's other co-chairman, Lee Hamilton, said that relationship "really does need more investigation."

"It is our view that Al Qaeda planned this operation and carried it out by themselves," added Hamilton, a former Democratic representative from Indiana.

Former Justice Department prosecutor John Loftus told FOX News that it is no secret Iran funded and housed training schools, like the Mashad school, for terror groups such as Al Qaeda, Lebanese Hezbollah and Palestinian Islamic Jihad. Al Qaeda members got to use the schools for free, Loftus said.

"Iran is the last rogue state really funding Al Qaeda," he told FOX News. "They're doing a pretty good job of this. It's more than just telling the border guards, 'When the Al Qaeda guys come through, don't put a stamp on their passport so they can't trace them back to Iran.'"

"This was knowing, willful assistance," Loftus said. "This is a notch higher, something that the intelligence community missed."

Loftus, who had access to some of the highest security clearances when he was a prosecutor, said that the June 1996 Khobar Towers bombing in Saudi Arabia was planned in Iran by Al Qaeda and Lebanese Hezbollah operatives. The bombings killed 19 U.S. soldiers and wounded 372 more.

"The Saudis were trying to cook together a deal with Iran saying, 'You keep the Al Qaeda out of Saudi Arabia and we won't tell the Americans that you, Iran, were one of the evil partners behind the Khobar Towers attack,'" Loftus said. "[The] Saudis have learned that you can't make a deal like that. It's a devil's bargain."

No Evidence of an 'Official Connection'

Interim CIA Director John McLaughlin said on FOX News Sunday that it was not surprising that eight of the Sept. 11 hijackers passed through Iran.

"Iran has been on the list of state sponsors of terrorism for many years," McLaughlin said. "Iran is the place where [Lebanese] Hezbollah, an organization that killed more Americans that Al Qaeda before Sept. 11, draws its inspiration and its finances."

He said the United States has "ample evidence" of people of ill repute allowed to move throughout Iran.

"However, I would stop there and say we have no evidence that there is some sort of official sanction by the government of Iran for this activity," McLaughlin said. "We have no evidence that there is some sort of official connection between Iran and Sept. 11."

Bush Vows to Continue Checking Iran Connection

President Bush said Monday the United States was exploring whether Iran had any role in the Sept. 11 attacks.

"We're digging into the facts to see if there was one," Bush said in an Oval Office photo opportunity. "We will continue to look and see if the Iranians were involved ... I have long expressed my concerns about Iran. After all, it's a totalitarian society where people are not allowed to exercise their rights as human beings."

Defense Secretary Donald Rumsfeld said it had been known that there were senior Al Qaeda members in Iran "for some time" and that Iran had been helping Lebanese Hezbollah in moving terrorists down through Syria into Lebanon, then down into Israel.

"So we know that Iran has been on the terrorist list," Rumsfeld said. "We know that Iran has been notably unhelpful along the border of both Afghanistan and Iraq."

Some experts wonder whether Tehran will be the next U.S. target in the War on Terror. Loftus said one option the United States could utilize to put pressure on Iran to stop its supposed dirty deeds — such as allegedly trying to make nuclear weapons — would be to establish a naval blockade.

American and British officials may ask the United Nations for action against Iran, Loftus added. Meetings are planned for September and November on the topic.

"My suspicion is, in September we'll really have evidence that Iran is lying through their teeth," Loftus said. "We'll put in a naval blockade and without oil exports, in three weeks the economy of Iran will collapse and it will either be neutered or there will be a regime change from within."

"We're not going to invade Iran but [are] probably going to blockade it with the full backing of the United Nations," he continued. "That's what is in store for the fall."

FOX News foreign affairs analyst Alireza Jafarzadeh noted that besides the Sept. 11 report detailing the known Iran-Al Qaeda ties, Iraqi officials have said Iran is the main source of foreign fighters behind the insurgency in Iraq.

"I think it all boils down to what policy the U.S. wants to pursue to contain the threat of Iran's nuclear weapons and the bigger problems Iran is posing," Jafarzadeh said. "They [U.S.] should pursue a zero-tolerance policy."

FOX News' Bret Baier and Trish Turner contributed to this report.