Did you witness an assault that took place on a train at the weekend?
Between 6.30pm and 7.30pm on Saturday (27 April) on an East Midlands Railway service travelling from Newark Castle to Lincoln a man threw food at a fellow passenger before racially abusing him and threatening other people on the service.
Officers are appealing for anyone who witnessed the incident to get in touch quoting reference 619 of 28 April.
Alternatively you can call Crimestoppers anonymously on 0800 555 111.