A twelfth suspect was identified by Greek police on Saturday in connection to a mob attack against Thessaloniki mayor Yiannis Boutaris on May 19.
The 22-year-old Greek national will face charges of verbal assault and disturbing the peace.
Three more suspects, aged 20, 21 and 34, were detained by police on Friday. The two younger men are charged with aggravated damages, as they were allegedly identified in videos kicking and smashing the windows of the car Boutaris entered to escape his attackers.
On May 23, a court found three men guilty over the assault. Two of the accused, aged 20, were handed a 14-month and 21-month suspended prison sentence respectively, while the 36-year-old ethnic Greek from Georgia received a 14-month jail sentence, which he was allowed to buy out for five euros per day.
Boutaris was assaulted by suspected far-right extremists during a commemoration of the World War I genocide of the Pontic Greeks in Thessaloniki.