Southeastern trains from London Bridge to Crayford and Barnehurst are being delayed this morning due to signal problems at Lewisham.
Tickets being accepted on DLR services.
Some lines are blocked and trains may be delayed by up to 15 minutes or diverted.
Southeastern expect disruption to continue until around 11.15am.
Yesterday, services were disrupted by a burglar hiding in a tree for 17 hours.