An unexploded WWII bomb discovered near tracks leading to France's busiest train station has severely disrupted rail service as police work to disable the device.

French police closed traffic to and from Paris Gare du Nord train station on Friday after an unexploded World War II bomb was found on tracks leading to the terminal, according to AFP and local media.

The discovery of the unexploded WWII bomb outside of Paris caused all Eurostar traffic coming in and out of Gare du Nord station to be “completely halted,” the railway company told PEOPLE in a statement.