Pierre Delalande from Eurostar said four trains in and out of England were affected, but that three of those had now reached their destination of London, while one was forced to turn back to the capital.
Trains do not run during the night and a full service is expected to resume this morning.
Mr Delalande said:
Four trains were affected - two from Paris to London, one from Brussels to London and one from London to Paris.
The only one that didn't make it was London to Paris because of a delay after the lightning, so went back to London.
Customers were offered taxis and hotels where necessary, he added.
Eurostar has confirmed that a lightning strike close to the UK entrance of the Eurotunnel has set a building on fire. As standard procedure, Eurostar services have been stopped until the fire is brought under control. Fire services are at the scene, but the flames are not yet under control.
4 trains have been affected by the fire. 1 London to Paris train has turned around and been sent back to London. 2 Paris to London trains and a Brussels to London train are still being held at either end of the tunnel, but are said to be moving "soon". No trains are being held in the tunnel.
5 railway substations are on fire this evening after a lightning strike near Folkestone in Kent. Firefighters are tackling the flames along the line from Dover priory to Sandling station. Hundreds of passengers have faced long delays due to signalling problems since just after rush hour.