A Canadian man yelled “Allahu akbar” before he allegedly stabbed a police officer at the Flint, Michigan, airport in what the FBI is investigating as a terrorist act, officials said.

Amor Ftouhi, 50, was charged with violence at an international airport, acting US Attorney Daniel Lemisch said in a statement. Ftouhi is accused of stabbing Lt. Jeff Neville with a roughly 12-inch knife with an 8-inch serrated blade Wednesday morning.

He had his initial court appearance late Wednesday afternoon and will remain in custody pending a full detention hearing next week, a US District Court official said.

Ftouhi, who entered the United States legally in Lake Champlain, New York, on June 16, walked into a public area on the first level of Bishop International Airport, carrying two bags. But he wasn’t an airline passenger, Gelios said. He lingered about 40 minutes, including time in a restaurant, before attacking Neville, a criminal complaint said.

“He spent a little time in the restroom, dropped both bags and came out, pulled out a knife, yelled ‘Allahu akbar’ (God is the greatest) and stabbed Lt. Neville in the neck,” Gelios said.

After stabbing Neville, Ftouhi continued to yell “Allah” several times, the complaint said.

He also said something similar to “you have killed people in Syria, Iraq and Afghanistan, and we are all going to die,” the complaint said.

A law enforcement officer subdued Ftouhi, who asked the officer why he did not kill him, the complaint said.

Ftouhi could face up to 20 years in prison and more charges could be added, officials said. It wasn’t immediately clear whether Ftouhi had an attorney.

Neville, who was stabbed in the main terminal, was in satisfactory condition, said Chief Chris Miller of the Bishop Airport Safety Division. Neville had worked at the airport for years and rose to the rank of lieutenant in 2006, according to airport director Craig Williams.

“Lt. Neville got him to stop stabbing him,” said Miller, who was nearby during the attack. “Lt. Neville fought him right to the end, right until I was able to handcuff this person.”

Officials said a maintenance worker was injured while helping to subdue the suspect. The employee was taken to the hospital with arm injuries and later released.

The airport, which was evacuated, later reopened.

Described as a lone-wolf attack

A law enforcement official said the stabbing appears to have targeted law enforcement.

“Based on the information we have presently, we don’t believe that anyone was involved with this individual. We have no information to suggest a wider plot,” Gelios said, adding that the investigation is in the early stages.

He added: “Time will tell over the next several days whether anyone had any knowledge of this, but at this time we view him as a lone-wolf attacker”

Gelios said there is no information that suggests Fthoui had any specialized training.

Authorities interviewed Fthoui extensively after the attack.

“I think it’s sufficient to say he has a hatred for the United States and a variety of other things, which in part motivated him towards coming to the airport today to conduct this act of violence,” the FBI special agent said.

Gelios said authorities are also trying to piece together Fthoui’s whereabouts since he entered the United States last week.

President Donald Trump was briefed on the attack, an administration official told CNN.

Suspect’s Montreal residence searched

Ftouhi is a Canadian citizen, according to Minister of Public Safety Ralph Goodale, CBC News, a CNN news gathering partner, reported.

A US official told CNN that, based on preliminary information, it appears Ftouhi has traveled between the United States and Canada multiple times.

A spokesperson for the Canadian Embassy in Washington said its government and law enforcement agencies are “engaged and are cooperating fully” with their American counterparts.

Police in Montreal went to Ftouhi’s apartment, CBC News reported.

Luciano Piazza, the building’s owner and Ftouhi’s landlord, said Ftouhi moved into the apartment with his wife and children five years ago. Piazza said he was “very surprised” to hear that Ftouhi was charged in the attack.

“He’s a good person, very quiet. I’ve never had any problems with him,” Piazza said, CBC News reported.

Fthoui had briefly studied for several months in 2011 to become an insurance representative in Montreal, according to statement from his former employer Industrial Alliance. But he left the company before obtaining his certificate and was never a company representative, the statement said.

Michigan Gov. Rick Snyder and Flint Mayor Karen Weaver gave words of support for the officers.

“(P)lease keep the attacked officer in your thoughts & prayers,” Snyder said on Twitter.

“My thoughts and prayers are with all of our law enforcement officers who work to service and protect us each and every day,” Weaver said in a statement.

The airport’s police department has six full-time and six part-time police officers. About 800,000 passengers took flights through Bishop last year, according to statistics from the airport.