Welcome to the news hour. Just hours before the Olympics opening ceremony,

Saboteurs launched a coordinated arson attack on French train lines.

It stranded nearly a million travelers and sparked even more concerns about

potential threats to the games which are being protected by

unprecedented security. Nick Schifran starts our coverage.

In Paris train stations this morning Nick Schifren starts our coverage.

In Paris train stations this morning,

crowds and confusion after coordinated attacks

on France's high-speed rail lines.

The overnight sabotage severed signaling cables that controlled the northbound,

westbound, and eastbound lines. A fourth attack on the southbound line was foiled.

Prime Minister Gabriel L'etal said the perpetrators knew what they were doing.

This operation has been prepared, coordinated, and key points have been targeted, which shows

a certain knowledge of the network in order to know where to hit. but acknowledge the games face threats.

45,000 police, 18,000 soldiers,

and 18,000 security contractors have created a huge security perimeter

and closed Paris's airspace within 90 miles.

In April, French President Emmanuel Macron inaugurated the Aquatic Center and warned of one possible

perpetrator, Russia.

You can do it too. I have no doubt, Russia. You can do too.

I have no doubt, yes, I have no doubt, including in informational terms.

Every day it fuels rumors about the fact that we could not do this or that so it would be a risk.

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