Josiah Brown, 19, of Wilmington, Delaware, was arrested Wednesday by federal agents and Delaware State Police troopers.
CNN is attempting to locate attorney information for Brown. Scanlon was physically unharmed during the incident.
According to the federal criminal complaint, Brown and other unidentified accomplices were in Philadelphia on Wednesday. At least one of them saw and approached Scanlon, identified as “M.S.” in court records, pointed a gun at her and demanded her car keys, the complaint said.
The group then drove to Delaware, where the vehicle was later located, and Brown was arrested. During an interview after his arrest, Brown “provided a written apology to the victim, indicating that he was sorry for stealing the car and for pointing a gun at her,” according to the criminal complaint.
Authorities have not said whether Scanlon was targeted as a member of Congress, but an FBI official indicated that the victim was a “total stranger” to the suspects in the Justice Department statement. Court records do not indicate Brown is being charged with assaulting a federal official.
“The investigation into this incident is in its very initial stages, and we are continuing to investigate and evaluate charging decisions,” said US Attorney Jennifer Arbittier Williams.
Brown appeared before a magistrate judge on Thursday, according to prosecutors, and remains in federal custody.
Authorities also took four other suspects into custody in connection with the incident, who have been charged with receiving stolen property, Senior Cpl. Jason Hatchell of the Delaware State Police told CNN Wednesday night.