The tourist who was filmed apparently carving his name into a wall of Rome’s 2,000-year-old Colosseum late last month has sent a letter of apology to the local prosecutor’s office, his defense lawyer told CNN on Thursday.

“I admit with the deepest embarrassment that only after what regrettably happened, I learned of the antiquity of the monument,” the alleged perpetrator wrote in his letter to the prosecutor, his lawyer, Alexandro Maria Tirelli, told CNN. The tourist’s name is Ivan Dimitrov, his lawyer told CNN.