Greek prosecutors on Thursday charged three more railway officials in connection with the country's worst train crash, as the prime minister vowed "absolute transparency" in the probe into the tragedy.

Nine days after the disaster, which claimed the lives of 57 people, distraught mourners gathered for a religious ceremony near the site of the accident.

Public anger has soared since the February 28 head-on collision in central Greece. Tens of thousands demonstrating nationwide on Wednesday, and there were more protests on Thursday.

The stationmaster on duty at the time of the accident, who allegedly directed both trains onto the same track by mistake, was charged several days ago.

On Thursday, a rail supervisor responsible for staff rotas -- accused of having put the inexperienced stationmaster on night duty during a busy holiday period -- was charged by a prosecutor in the central city of Larissa, a judicial source told AFP.

Also charged were two other stationmasters, who reportedly left work early. All three face counts of negligent manslaughter, causing bodily harm and transport disruption, and could face life in prison if convicted.

'Crying from morning to night'

The conservative leader, who is expected to run for re-election in the coming months, also promised "immediate actions to improve the problematic situation in the railways".

(AP)

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