79-year-old Aristophanes Mallis has been missing since the morning of Thursday, April 23, from the Monastery of Karakalos on Mount Athos.
On the day of his disappearance, he was wearing a gray cardigan, a blue shirt, black-gray sneakers and dark blue pants.
He is 1.63 tall, has white short hair and brown eyes.
The photo is recent and representative.
Silver Alert has been activated for his disappearance.