A person is believed to have been struck by a train near to Newark Northgate station, leading to lengthy delays for East Coast Main Line passengers.
Emergency services are dealing with the incident, and delays are currently expected to continue until 6pm.
According to National Rail, delays are up to 90 minutes.
It has issued the following information:
Hull Trains services may be diverted, not calling at Retford and Grantham. If you are travelling to Retford on one of the diverted services, change at Doncaster for a taxi service to Retford.
Alternative Travel Options for Virgin Trains East Coast passengers:
* CrossCountry services on any reasonable route
* East Midlands Trains services between London St Pancras International and Newark North Gate via Nottingham, and London St Pancras International and Doncaster via Sheffield.
* TransPennine Express between Leeds / York and Manchester.
* Virgin Trains between Scotland and London Euston.
Alternative Travel Options for Hull Trains and Grand Central passengers:
* You can use your ticket on East Midlands Trains services between London St Pancras International and Newark North Gate via Nottingham/Doncaster via Sheffield.