The FBI is investigating a double stabbing in Virginia Saturday night as a possible terrorist attack, CBS News reports. One law enforcement source told the CBS reporter that  the suspect yelled “Allah Akbar”—Arabic for God is Great—during the stabbing. Witnesses told police they heard the same thing, according to the CBS Roanoke affiliate.

Police told CBS that Wasil Farooqui, 20, of Roanoke County stabbed a man and woman in a random attack, leaving the victims hospitalized. Farooqui is charged with two counts of aggravated malicious wounding and is being held without bond.

The male victim fought off the attacker, police said. While officers were at the hospital with the victims, a man later identified as Farooqui visited the emergency room with injuries of his own, authorities said. He fit the description of the suspect in the stabbing, and further investigation by police led to his arrest, they said.

Farooqui has been on the FBI’s radar for months and is believed to be self-radicalized, CBS News reported. A source said Farooqui tried to go to Syria earlier this year but only got as far as Europe, then returned to the U.S. The trip is what put him on the FBI’s radar.