Object thrown at Caltrain in Redwood City hitting engineer

REDWOOD CITY, Calif. (KGO) -- A Caltrain engineer was struck by something thrown through the engineer-side window of a train in Redwood City. It happened around 6:30 Friday night.

Transit police and first responders were called to the scene. The train was taken out of service for the investigation.

There were 450 passengers on-board were put onto a different train.

It's unclear who threw the object, or how the engineer is doing.

We know medical assistance was requested.