Police officers are trying to track down vandals who hurled stones at a passenger train from a bridge in Mexborough - damaging a window.
The 6.55pm TransPennine Express train, travelling between Manchester Airport and Cleethorpes, was struck at 8.30pm on Thursday, April 7.
British Transport Police said vandals threw stones from the Ferry Boat Lane footbridge.
PC Alek Marinkovic said: “The stones smashed the outer skin of the front passenger side window.
“Fortunately no-one was injured but the driver was left extremely shaken by what happened.
“This type of reckless behaviour is criminal and dangerous and we would like your help in tracing those responsible. If you have any information please contact us.”
Call British Transport Police on 0800 405040 or text 61016, quoting reference 402 of April 15.
Information can also be passed to Crimestoppers on 0800 555 111.