Clashes took place at the protest rally over the Larissa train crash taking place tonight at Syntagma Square in Athens.
The Greek media report it.
The anti-riot units - called Mat - of the Greek police used sting gas and stun grenades, writes Efsyn.gr.
The crowd dispersed.
Demonstrations of protest and remembrance of the victims have been taking place since yesterday in various cities in Greece.
Railway accident in Greece, the moment of the head-on crash between the two trains
The incidents - reports an AFP journalist - began when a group of demonstrators broke away from the silent and peaceful march and threw stones at a group of police officers, who responded with tear gas.
Clashes subsequently also occurred in Amalias street, also in the center of Athens, writes efsyn.gr.
Tension and some minor incidents were also reported at the analogous demonstration in Thessaloniki.
