'Allah Akbar!' Possible ISIS inspired beheading in Virginia under investigation by the FBI

The FBI has launched a federal terrorism investigation into a weekend stabbing in Roanoke, Virginia, looking at whether the attacker may have been trying to behead his victim in an alleged ISIS-inspired assault, sources told ABC News.

Federal authorities have been aware of the alleged attacker, 20-year-old Wasil Farooqui of the Roanoke area, for some time, sources familiar with the case told ABC News. In the past year, sources said, he traveled to Turkey and may have tried to sneak into Syria, where ISIS is recruiting and inspiring sympathizers from around the world.

Farooqui was arrested Saturday by Roanoke County Police on charges of assault with malicious wounding, and he is being held without bond at the Western Virginia Regional Jail, according to the sources and a jail database.

On Saturday, Farooqui allegedly injured a man and woman at an apartment complex in Roanoke, yelling "Allahu akbar" as he attacked them with a knife, sources told ABC News.

Authorities believe he may have been trying to behead the male victim, who was likely picked at random, ABC News was told.

Farooqui and his two alleged victims were hospitalized after the attack. Their conditions were not clear.

"The FBI is working with the police department following the incident that occurred on Saturday evening," Adam Lee, the head of the FBI's Richmond field office and the special agent in charge, said in a statement. "While I cannot discuss details of the investigation at this time, I do want to reassure the community that we are working to determine the nature of the incident."