When the subject turned to terrorism during the March 3 Republican presidential debate in Detroit, Donald Trump called for being tough on the families of terrorists, not just the terrorists themselves.

As an example, he resurrected a claim he has made before — that the wives of the 9/11 terrorists knew what was going to happen and fled the United States to Saudi Arabia just before the attacks.

"A man flies in the World Trade Center and his family gets sent back to where they were going — and I think most of you know where they went and, by the way, it wasn't Iraq. But they went back to a certain territory. They knew what was happening. The wife knew exactly what was happening," Trump said.

"They left two days early with respect to the World Trade Center and they went back to where they went and they watched their husband on television flying into the World Trade Center, flying into the Pentagon and probably trying to fly into the White House except we had some very, very brave souls on that third plane."

During part of the response it sounds like Trump is talking about one wife, but he subsequently makes it clear that he's talking about all of the planes involved in the attack — actually there were four. So in the same breath he seems to be talking about multiple wives.

Trump was clearer during the December 15 GOP debate in Las Vegas when he said that friends, family, girlfriends "were put into planes and they were sent back, for the most part, to Saudi Arabia. They knew what was going on. They went home and they wanted to watch their boyfriends on television."

Regardless, Trump’s account of what happened in September 2001 doesn't stand up to scrutiny.

Of all the hijackers, not one had a wife, girlfriend or family member in the United States during the days or months leading up to the hijackings, according to the 9/11 Commission report .

Not all were pinpointed, but "they sure weren’t living in the United States," Philip D. Zelikow, executive director of the 9/11 Commission, told PolitiFact in mid-December.

In fact, only two of the 19 hijackers were married and only one had a girlfriend, and she was living in Germany.

The commission concluded that most of the 19 hijackers had "broken off regular contact with their families" long before the attacks, except for the hijacker with the girlfriend in Germany. He was on the plane that crashed in rural Pennsylvania. Investigators concluded after extensive interviews that she knew nothing about the plot.

Trump’s words might reflect some confusion with the hastily organized departures of members of Osama bin Laden’s extended family -- not any wives or girlfriends of bin Laden himself -- a few days after the attack.

Most of the bin Laden relatives were in high school or college in the United States. In an interview with the New York Times, Saudi Ambassador Bandar bin Sultan said that with the help of the FBI, his government arranged for these people to assemble in Washington where a chartered plane would take them back to Saudi Arabia.

But it seems clear Trump wasn't talking about them.

And the fact that some of those relatives were evacuated from the United States for their protection doesn't make what Trump said during the Fox debate any more accurate.

Trump's claim is False.