Police are hunting a gang of men who acted aggressively towards women on a York to Darlington train, leaving one of them injured.
The assault happened on board a TransPennine Express train travelling from York to Darlington.
At around 5.05pm on Saturday 4 May, British Transport Police received reports a group of men acting aggressively towards a group of women, before throwing an item which hit one of the women in the head.
They then left the train at Darlington.
Officers believe the men in the CCTV images may have information that could help their investigation.
Anyone who recognises them, or has any other information, is asked to contact British Transport Police by texting 61016 or by calling 0800 40 50 40 quoting reference 515 of 04/05/24.
You can also call Crimestoppers anonymously on 0800 555 111.