Nineteen people were injured on Thursday when a minibus carrying truck drivers crashed into a vehicle shuttle train at the French entrance to the Channel Tunnel near Calais.

Two people were hospitalised with serious but non-life-threatening injuries, French authorities said. The collision forced a 90-minute suspension of shuttle services.

The incident occurred on a Eurotunnel loading platform. A spokesperson described the sequence of events leading up to the crash.

"Two trains were on either side of the platform. One was being loaded by heavy goods vehicles ahead of a cross-Channel journey, and another train that had previously been loaded was departing," the spokesperson said.

"For a reason that currently remains unknown, the minibus collided with the departing train."

"The bus did not overturn, it is still upright -- but the shock and the collision caused injuries to the people involved."

The minibus was transporting workers who were about to board Le Shuttle. All were men of different nationalities, the spokesperson added. It is not clear whether any British nationals are among the injured.

The spokesperson described it as "the first time an incident of this type has occurred" on a Eurotunnel loading platform.

Photos published by local French newspaper La Voix du Nord showed a small bus with damage to its front and side standing alongside a train, surrounded by emergency workers.

A witness travelling through the Eurotunnel to Calais at the time of the incident reported seeing blue light vehicles "concentrated on one of the platforms" upon entering France.

"There were plenty of cars queueing up at check-in when I drove past just now, and I saw some cars going through check-in, so despite the collision they weren't being held," the witness said from the scene.

Eurostar issued a statement clarifying that its services were unaffected. "An incident occurred several kilometers away from the Channel Tunnel. This incident does not involve or impact Eurostar trains running from and to London. All of Eurostar trains will run as expected," the company said.