A train driver escaped injury after a brick was thrown at his windscreen from a bridge.
The 8.30 Norwich to London train was just leaving Diss station at about 8.50am when a brick or large stone the window, shattering the glass.
The impact left a crazed effect on the windscreen but no glass appears to have fallen out.
The driver managed to continue the journey to Ipswich, where the train was forced to terminate. Passengers were put onto the train behind.
Police are investigating.
The train's been taken to the Crown Point depot at Norwich where it is being repaired.
Lucy Wright from Greater Anglia said the driver was very professional and although he was shaken he was able to continue the journey.