TfL has removed 90 EV double decker buses from service as a precautionary measure following one vehicle being engulfed in flames on Sunday 22 May. 

The fire spread to engulf a total of six buses at the Potters bar Bus Garage and could be seen as far away as St Albans, Hertfordshire, nine miles away.

It is usual practice to remove vehicles from service after an incident such as this.  The cause which may have been a charging or battery error, as the vehicles are electric, is being investigated.  

There will be disruption to some service routes whilst the vehicles are removed from service for the investigation to be conducted.

https://www.mylondon.news/lifestyle/travel/tfl-instantly-removes-108-london-24033800