Hello, I'm Celia Hatton.

Welcome to News Hour from the BBC World Service coming to you live from London.

But we begin in Paris, the city that was meant to be gearing up for its moment in the sun today,

the head of the Olympics opening ceremony, starting in just a few hours time.

Instead, Paris is at the epicenter of travel chaos and a criminal investigation.

The country's National Rail Network, the SNCF, has been hit by a coordinated act of sabotage,

which it says is affecting 800,000 passengers.

Three main routes of the high-speed T. G. V. Line, serving the capital from the east, west, and north were set on fire. A further attack to the south was foiled.

This has led to severe disruption. Speaking to reporters, the deputy transport minister Patrice Verdriad gave this brief update on the investigation.

Today all the information we have clearly shows that it was deliberate.

The simultaneous nature, everything happened at the same time.

Vans were found from which people had fled, particularly in the southeast,

and sendry devices were found on site.

An investigation is underway.

Everything now points to the fact that these were arson attacks,

particularly the timing, which is more than suspicious.

But the President of the International Olympic Committee, Thomas Bach, said he had no security concerns. All the measures are being taken and the French authorities are assisted by 180 other intelligence services around the world and not only by information some of them are even

deploying their human resources and so we have good reasons to have full confidence.

And yet there are cancellations and severe delays.

Passengers stranded at Moldvana's station in Paris

express their concern and disappointment.

I'm not particularly afraid,

...