Trains between Sleaford and Ruskington have currently been suspended after a passanger reported seeing a body beside the tracks.
A spokesperson for British Transport Police said: “Officers are currently dealing with an incident near Ruskington railway station, after receiving a report of a body near the tracks.
“Colleagues from Lincolnshire Police and Lincolnshire Fire and Rescue are also in attendance.
“The report was received at 3.21pm from a passenger on a train travelling through the area. A search along the line is currently being undertaken but at this stage nothing has been discovered.
“Currently trains travelling on the line are suspended while the track search takes place. Passengers are advised to check with National Rail Enquiries before they travel.”
A statement from East Midlands Trains said: “Emergency services are dealing with an incident near Ruskington and this is causing delays of up to 60 minutes between Sleaford and Lincoln Central. There is no firm estimate yet of how long disruption will last but it is likely to continue until at least 5pm.
“Passengers may use their tickets on East Coast services between Peterborough and Newark North Gate.”