The train derailment that killed at least six people in central France may have been caused by a loose steel plate at a junction, French train operator SNCF said.
The steel plate, which should have remained bolted onto the track, moved to "the middle of the track junction", preventing the rolling stock from passing through, Pierre Izard of SNCF said today.
"The reasons why this fishplate dislocated itself is the very focus of the investigations," SNCF head Guillaume Pepy said.
More top news
Former shadow foreign secretary Hilary Benn led calls by a series of senior Labour MPs urging colleagues to 'win' back the party.
A team of detectives and specialists is set to begin a painstaking excavation of the area where Ben is thought to have gone missing in 1991.
The foreign secretary's suggestion last week's bombing of an aid convoy might constitute a war crime prompted an angry response from Moscow.