Greek league offices attacked with gas canisters
No one was reported injured in the incident, which took place in the Athens suburb of Marousi. The glass entrance doors and the window of a parked car were smashed, according to police.
Police said the incident was not considered a terrorist act, adding that it was likely linked to Saturday's derby match in which Olympiakos Pireaus defeated Panathinaikos 2-1 in controversial circumstances.
Ugly scenes followed the game in Piraeus when dozens of Olympiakos fans invaded the pitch to celebrate. Some aimed kicks and punches at Panathinaikos players.
The losers were enraged by several refereeing decisions, including one disallowed goal.