Two German nationals are among 13 suspects who have been arrested over rioting in central Athens that broke out on Thursday night during a march marking the 10th anniversary of the police killing of teenager Alexis Grigoropoulos in the neighborhood of Exarchia. The suspects also include three minors who were arrested earlier on Thursday during scuffles with police at a student rally in memory of the 15-year-old. In the northern port city of Thessaloniki, meanwhile, police have arrested 15 people aged 16 to 27 for similar violence during a demonstration for the anniversary. Of them, two are minors and two are foreign nationals, police said. In Exarchia, the epicenter of the overnight rioting, municipal cleaning crews faced a daunting task on Friday morning, as the streets were strewn with debris, ash and tear-gas residue from the clashes between self-styled anarchists and riot police, while dozens of cars, dumpsters and buildings were also damaged. At Thessaloniki’s Aristotle University, meanwhile, authorities are assessing the damage caused to the Department of Philosophy, which was overrun by anarchists using it as a launching pad for their attacks against police, saying that repairs will likely cost in excess of 10,000 euros.