A “casualty on the track” brought trains on the Victoria Line to a standstill on Sunday.
Transport for London (TfL) said there was no service on the line between King’s Cross St Pancras and Seven Sisters while emergency services dealt with the incident.
It added that Finsbury Park station had been closed shortly after 4pm on Sunday. The station later reopened at around 5.50pm.
Meanwhile, there were severe delays on the rest of the Victoria Line.
In an update, TfL said that tickets were being accepted by London Buses as well as on the Weaver Line and the Suffragette Line.
Great Northern, Thameslink, Greater Anglia, South Western Railway and Southeastern services were also accepting tickets.
A post on TfL’s website said: “No service between King's Cross St. Pancras and Seven Sisters while emergency services deal with a casualty on the track.”
The emergency services have been contacted for comment.
