The incident happened at Chadwell Heath station
Officers from the Met had attempted to stop a van in nearby Burlington Gardens at around 9.45pm last night.
But the driver failed to stop and was pursued by officers.
At Chadwell Heath station, the man got out of the vehicle, ran into the station, and then onto the track.
The incident caused disruption, with TfL Rail trains and Greater Anglia both unable to pass through the station while it was ongoing.
NEW: Due to a trespass incident between Romford and Chadwell Heath the line is blocked.
Trains are not running to allow BTP and Network Rail staff to get the person off the track safely.#Romford
— Greater Anglia (@greateranglia) July 12, 2020
Police searched the area but the unable to find the suspect.
Train lines reopened shortly before 11pm.
Tags: Chadwell Heath, Barking and Dagenham, TfL Rail, Greater Anglia, Public Transport