CHICAGO (AP) — A Chicago man who allegedly spat into the face of an FBI special agent and then told him there was no proof because the incident wasn’t captured on video was arrested in part due to an account by a witness.

The 55-year-old was arrested on a charge of assaulting an agent and booked into the Metropolitan Correctional Center, according to a criminal complaint unsealed Monday, the Chicago Tribune reported.

The man remained in custody Tuesday and it could not be immediately determined whether he had an attorney.

The alleged incident happened Jan. 12 near the FBI’s field office in Chicago. According to the criminal complaint, the man pulled his van behind a car driven by the FBI agent, who was waiting to enter a parking lot, and started to repeatedly honk his horn.

When the agent told him to stop honking, the man told him that he was honking at another vehicle — an SUV — but became angry when the agent refused to talk to the driver, and told the agent: “If you’re such a tough guy, get out and show me,” according to the complaint.

When the agent refused to get out, the man allegedly used profanity and then leaned toward the open driver’s side window of the agent’s vehicle and spat into his face. “Good luck proving it,” he allegedly told the agent. “There’s no video.”

The driver of the SUV, however, witnessed what had happened, according to the criminal complaint, and the agent photographed the 55-year-old’s vehicle and license plate as further evidence.