Source (greek only): http://news.pathfinder.gr/greece/news/434581.html - http://www.ethnos.gr/article.asp?catid=5592&subid=2&pubid=48619
A little before 22:00 around 20 persons wearing hoods attacked two banks (one "Ethniki" and one "Agrotiki" bank) in Ilisia area in Athens. They broke the glass windows and threw molotov cocktails inside the banks. They all managed to escape police forces and run to the Zografou university area.
Later on, the police arrested eight persons but left them free because they found no evidence, except from one of them that carried a wooden glob and will be prosecuted.