Eurostar trains to London and all trains heading to northern France were brought to a halt Friday following the discovery of an unexploded World War II era bomb on tracks leading to the nation’s busiest station.

Eurostar trains between London and Paris have been cancelled after the discovery of an unexploded bomb dating back to the Second World War near the tracks.The unexploded bomb was reportedly found by workmen overnight in the Paris neighbourhood of Saint Denis.

All 32 trains scheduled to run between London and Paris on Friday have been cancelled, wrecking travel plans for thousands of passengers. But extra services have been added to Saturday's timetable.