A suspect package is being investigated by officers at Walthamstow bus station.
The package was found around 9:30am and the immediate area was evacuated.
Walthamstow Central station has also been closed, along with Selbourne Road and Hoe Street.
Police say the pakcage is being looked by police and specialist explosive officers are at the scene.
London Ambulance Service have a vehicle on standby at the scene.
Several trains have been cancelled and bus routes diverted.
Reports that the incident is now over are yet to be officially confirmed.