Minor clashes have broken out between Greek police and stone-throwing youths during an Athens protest march in memory of an activist musician killed by a far-right person four years ago.

Police used stun grenades to disperse the rioters during Monday's clashes in the capital's western suburb of Keratsini.

No injuries or arrests were reported. Youths smashed the windows of a local municipal building, and threw at least one petrol bomb at police. About 2,200 people took part in two separate marches organized by left-wing groups.

A similar protest Sunday in central Athens ended in violence, with riot police using tear gas against protesters attacking them with petrol bombs. One detained youth was injured after being struck by a car while trying to escape from custody.