STORY: A local train station master has been arrested over the deadliest train crash to hit Greece in living memory.

The man is denying any wrongdoing and has attributed the accident to a possible technical failure, according to government and police sources.

The passenger train and a cargo train collided head-on on Tuesday night (February 28) outside the city of Larissa, killing dozens and wounding more.

Many of the victims are thought to be university students on their way back from a long holiday weekend.

Fire officials say the death toll is expected to rise further.

The passenger train was carrying over 350 people and heading to the city of Thessaloniki, on the Aegean coast, according to Hellenic Train data.

The government has declared three days of national mourning, with flags at half-mast.

Greece's Prime Minister Kyriakos Mitsotakis visited the crash site on Wednesday (March 1).

He's describing it as "an unspeakable tragedy" and the government will do everything in its power to make sure it never happens again.

Greece's ageing railway system is in need of modernizing and many trains travel on single tracks.

Rail signals and automatic control systems still need to be installed in many areas.