Travellers heading between Penkridge and Stafford were forced to make other arrangements after the West Coast Mainline was closed between the two stations on Saturday.
Emergency services were called to an area near Stafford around 1.30pm following reports of an incident, with British Transport Police in attendance.
Rail replacement bus services were running between Wolverhampton and Crewe and other train services were accepting tickets for London Northwestern passengers.
The line was subsequently reopened at 3.15pm
A London Northwestern Railway spokesperson said: "Services through Stafford were subject to delays and cancellations on Saturday afternoon while the emergency services dealt with an incident on the railway.
"Any passengers whose journeys were delayed by 15 minutes or more can claim compensation via the Delay Repay scheme."
British Transport Police, West Midlands Ambulance Service and Staffordshire Police have been contacted for a comment.