Tens of thousands of passengers and commuters struggled to reach their destinations on Saturday, on the second day of train disruptions due to acts of sabotage which targeted French trains on the opening day of the Olympics.

French Transport Ministry authorities said some 160,000 of the 800,000 passengers due to travel this weekend continued to face cancellations, with nearly a third of trains in France's northern, eastern and western regions not running.

Eurostar also said around a quarter of its high-speed trains between Paris and London were canceled.

Services would be back to normal by Monday, said French rail company SNCF chief Jean-Pierre Farandou.

Foreign involvement not ruled out

A claim of responsibility for the attacks has yet to be made.

Security sources told the Reuters news agency on Friday that leftist militants or environmental activists were the initial suspects, as per the modus operandi. There was, however, no evidence yet to confirm those groups as the perpetrators.

French Interior Minister Gerald Darmanin said Saturday the investigation was progressing.

"We have uncovered a certain number of elements that allow us to think that we will soon know who is responsible for what clearly did not sabotage the Olympic Games but did sabotage part of the holidays of the French people," Darmanin told France 2 television.

He added that he could not rule out foreign involvement.

"Who is responsible? Either it's from within, or it's been ordered from abroad, it's too early to say," he said.

What we know about the acts of sabotage

The meticulously planned attacks early Friday morning hit the cabling boxes of the country's high-speed rail network junctions north, southwest and east of Paris. The cables transmit safety information to train drivers.

The attackers also set the cables on fire.

A fourth attack on the line connecting the capital to the southern city of Marseille was prevented.

The SNCF said its staff worked through the night "in difficult conditions in the rain" to get the affected lines working again.

"Everything will be back to normal for Monday morning," Farandou told reporters at Paris Montparnasse station. "We will be ready."

Passengers were given regular reminders via loudspeakers that trains would be canceled or delayed due to a "a malicious act."

Some three in every 10 trains were canceled on Saturday in the three affected regions, with the majority of running trains facing delays of between an hour and two, the SNCF said.

rmt/wd (AFP, Reuters)