Former FBI agent made chilling 7-word premonition just days before dying in 9/11 attack

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A former FBI agent who'd repeatedly warned of the likelihood of a major terrorist attack in the US made a chilling comment to his friend days before he died in 9/11.

In 1993, al-Qaeda attempted to take down the World Trader Center detonating a bomb hidden in a van underneath the North Tower - it resulted in the death of six people.

At that point John O'Neill was an FBI agent and it spurred him on to learn more and more about terrorism.

His heroics were mentioned in the 9/11 Memorial & Museum: "Through his self-education, O’Neill would become the FBI’s top terrorism expert and its authority on Osama bin Laden.

"His warnings about the terrorist threat to the US homeland often fell on deaf ears."

Yes, O'Neill sensed something bad was looming.

A memorial was held for the former FBI agent John O'Neill who died a hero (Tim Boyle/Getty Images)

Four years prior to the attacks he told the Associated Press: “A lot of these groups now have the capability and the support infrastructure in the United States to attack us here if they choose to do so."

And the very next month gave a speech in Chicago to an audience at the National Strategy Forum. He said: “I think interesting times lie ahead. Certainly, we as citizens will be challenged.

"I know the FBI will continue to be challenged in the years to come.

"Unfortunately, I cannot predict that no Americans will be injured or killed as a result of a terrorist attack.”

After 31 years of service he retired from the FBI in August 2001.

Just two weeks later he took on a new role as chief of security at the World Trade Center - it was here that he met his end when the South Tower collapsed.

In the days leading up to the attack he gave a chilling seven-word premonition to his friend, ABC News producer Chris Isham.

O'Neill was crushed by the South Tower when it collapsed (Andrew Lichtenstein/Corbis via Getty Images)

Speaking about the Twin Towers' vulnerability to terrorist attacks, Isham joked: "At least they’re [al-Qaeda] not going to bomb it again."

To which O’Neill replied: "They’ll probably try to finish the job.”

After the first plane struck the North Tower he called his son to inform him that he was OK and not to worry, he then helped with evacuations.

The American hero's body was discovered in the rubble 10 days later.

On Tuesday September 11, 2001, 19 terrorists from al-Qaeda took over four planes and spread utter devastation across the United States - crashing two into the World Trade Centre in New York City, one into the Pentagon in Washington D.C, and another into a field in Pennsylvania (the intended target is believed to have been the Capitol building).

2,977 innocent people lost their lives that day.