ATHENS, Greece (AP) — Greek police say a senior traffic police officer has been beaten up by unknown youths after the end of a protest march by anarchists and left wingers in Athens.

The head of the Athens traffic police was hospitalized with minor injuries after the attack in the city center on Monday evening. Police said he was assaulted by five youths as he was walking on a main street after supervising traffic measures for the demonstration.

About 800 people took part in the march, held to protest an arson attack on a left-wing squat used to house refugees and other migrants trapped in Greece.