The man who stabbed an airport policeman at Bishop International Airport in Flint tried to unsuccessfully buy a gun in the U.S. before Wednesday's attack, FBI officials said today.

Special Agent in Charge David P. Gelios also told reporters that Amor Ftouhi, a resident of Canada, was in Michigan as early as June 18.

He first entered the U.S. through New York June 16.

Ftouhi, 49, yelled “Allahu Akbar,” meaning “God is great” in Arabic, pulled out a knife and stabbed Lt. Jeff Neville in the neck in a public area of the Bishop International Airport. The attack took place at 9:45 a.m.

He has been charged with committing an act of violence in an international airport, which carries a penalty of 20 years behind bars.

Authorities have interviewed more than 20 witnesses in connection with the ongoing investigation, Gelios said. They believe Ftouhi acted alone.

"We continue to have no information to suggest Fthoui's attack on Lt. Neville was part of a wider plot," Gelios told reporters today.

Gelios said Ftouhi tried, but failed, to purchase a gun in the U.S. He declined to say where he tried to buy it.

The knife used in the attack was purchased in the U.S., Gelios said.

Neville is in stable condition.

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