Image source, PA Media

As we get more details about Eurostar diverting all its services to and from Paris in France today, we're seeing pictures of long queues at St Pancras International station in central London.

Services from London to Paris are operating but passengers can expect journeys to be an hour longer, the rail operator said in a statement.

Some trains have also been cancelled such as the 15:31 service to Paris, as a sign in the London station shows below.

Image source, PA Media

Image source, Reuters

The disruption comes hours ahead of the opening ceremony for the Paris Olympics, where thousands of athletes are set to sail through the heart of the city in boats.

A flotilla will carry more than 10,000 athletes along the River Seine in a route dotted with the city's major landmarks, in front of 300,000 spectators and an audience of VIPs and celebrities.

The four-hour ceremony, set to begin at 18:30 BST, marks the first time a Summer Olympics has opened outside the main athletics stadium.

While many of the details have been kept under wraps, it's rumoured that Canadian singer Céline Dion, Pop star Lady Gaga and French-Malian R&B star Aya Nakamura could be among the performers.

Organisers hope the spectacle is free-flowing, amid a mammoth security operation that involves a massive security perimeter along both banks of the Seine, guarded by 45,000 officers and gendarmes. Another 10,000 soldiers as well as 22,000 private security guards are also deployed for the event.

We're receiving our first images about some of the disruption that is taking place around the country.

This sign, in Paris's Gare du Nord informs passengers that high speed trains are interrupted between Paris and Lille following a malicious act in the area of Arras.

It warns of changes to routes and subsequent delays to journeys.

Image source, Reuters

The president of the SNCF group has just spoken with the French news outlet BFMTV.

He says that 800,000 customers have been affected.

He adds that the network was prepared for the Olympic Games but that they are now looking at mobilising hundreds of personnel to fix the network as quickly as possible.

Eurostar services in France to and from Paris are being diverted and several trains have been delayed, the rail firm says in a statement.

The high speed line between Paris and Lille has been affected while journey times have increased by 90 minutes following "co-ordinated acts of malice in France", it says.

Several trains have been cancelled, it adds.

Trains between Paris and London are still running on "classic" lines but passengers can expect journey times to be an hour longer.

Image source, Reuters

In the last few moments France's state-owned SNCF company has warned rail passengers who can postpone their trip to do so.

SNCF is advising travellers "not to go to the station" - a reminder only the Atlantique, Nord and Est lines of the TGV network are impacted.

The Atlantique goes from Paris to Bordeaux, the Nord goes from Paris to Lille and the Est takes passengers from Paris to Strasbourg.

The rail firm says tickets for these disrupted journeys are exchangeable and refundable.

"Following this massive attack aimed at paralyzing the high-speed line network, a large number of trains were diverted or cancelled," SNCF reiterates in a social media post.

Hugh Schofield
Reporting from Paris

SNCF says it’s been a victim overnight of a "massive attack aimed at paralysing the network”.

Fires were started at three points on TGV lines running west, north and east of Paris.

A fourth arson attack on the line running south to Lyon and the Mediterranean was foiled.

The result is that TGV trains are being diverted onto other lines, leading to delays of up to two hours and some cancellations.

Repairs will not be completed until after the weekend.

No claim of responsibility has been made but it is hard not to see a link with the Olympic Games.

This was always going to be a very busy day in Paris stations, with visitors arriving for the opening ceremony in one direction, and in the other many Parisians leaving at the start of their summer holiday.

We're beginning to see some further details about what happened overnight to the rail networks in Paris.

AFP news agency has just reported comments they have received from a source close to the investigation who says the arson attacks were acts of "sabotage".

Their source added that the attacks were "evidently co-ordinated", according to the news agency.

Image source, Getty Images

Let's bring you some comments from the French transport minister, who has strongly condemned "criminal acts" following vandalism on the rail network overnight.

Posting on social media Patrice Vergriete wrote: "Co-ordinated malicious acts targeted several TGV lines last night and will seriously disrupt traffic until this weekend.

"I strongly condemn these criminal actions which will compromise the vacation departures of many French people."

Vergriete went on to thank SNCF staff on trying to restore services "as quickly as possible".

Hours ahead of the Olympic Opening Ceremony in Paris, the French railway company SNCF says it's been hit by a series of "malicious acts" aimed at paralysing its high speed network.

"Last night, the SNCF was victim of several acts of vandalism on the Atlantic, Northern and Eastern high-speed lines. Fires were deliberately set to damage our installations," the SNCF said in a statement.

French rail company SNCF says its high-speed network has been targeted by "malicious acts" aimed at paralysing the system.

It comes hours before the opening ceremony for the Paris Olympic Games.

Several high-speed TGV lines have been hit to the west, north and east of Paris and queues have formed at Gare Montparnasse station in the city.

A number of trains have been cancelled and SNCF has warned that the situation could last "at least all weekend while repairs are conducted".

Stay with us as we bring you live updates.