The Federal Bureau of Investigation is looking into what could be deemed a terrorist act that took place in in Queens, New York, on Thursday. Zale Thompson, 32, is suspected of attacking four New York City Police Department officers with a hatchet while they posed for a photograph. Two cops were wounded before the police fatally shot the suspect, accidentally hitting a 29-year-old female bystander.

“This matter has not officially been deemed an act of terrorism as the initial investigation is still ongoing and details are being developed,” the FBI said in a statement.

The suspect wounded 25-year-old Kenneth Healey in the head and 24-year-old Joseph Meeker in the arm, New York City Police Commissioner Bill Bratton said at a press conference. Healey is still in critical condition and was undergoing surgery at a hospital in Queens. Meeker was expected to be released Thursday night.

"Unprovoked and not speaking a word, the male then swung at one of the officers with a hatchet, striking his right arm,” Bratton said. “After striking that officer, the suspect continuing swinging the hatchet, striking a second officer in the head."

Bystanders filmed the attack on their cellphone cameras.

Thompson’s Facebook page reportedly contained “images of what appears to be a Muslim warrior and prayers,” MSNBC reported. International Business Times was not able to independently confirm the authenticity of the page.

The FBI has been on high alert and has warned border officials to remain vigilant following two separate terrorist attacks in Canada this week. Canadian Michael Zehaf-Bibeau is suspected of opening fire at Canada’s parliament in Ottawa on Wednesday, killing a Canadian soldier and wounding several others.  Earlier in the week, Martin Couture-Rouleau carried out a fatal hit-and-run attack on two Canadian military men in Quebec.