French rail services were due to return to normal on Monday following emergency work to repair damage caused by suspected arson attacks on Friday.
The apparently coordinated attacks which coincided with the start of the Olympic Games in Paris targeted fibre optic cables on a number of high-speed TGV lines, impacting SNCF and Eurostar services.
SNCF said around a quarter of a million passengers were impacted on the day, while France’s transport minister said up to 800,000 could be affected before services returned to normal.
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Eurostar was forced to cancel four of 15 services between London and Paris over the weekend and encouraged affected passengers to postpone their trips if possible, with no alternative seats available.
SNCF confirmed repair work had been completed on Sunday, with a full service due to resume today (Monday).
There were no service issues reported by Eurostar as of 7.15am on Monday.