Travellers are being warned to expect delays after a person was hit by a train at Ilford.
All trains have been stopped in the Ilford area but some lines have now reopened.
Trains will be cancelled, delayed by up to 60 minutes, or revised at short notice.
Transport for London Underground services are taking passengers via any reasonable route until further notice.
Arrangements have been made for Abellio Greater Anglia rail tickets to be accepted for these journeys.