Emergency services were called to Main Road in Romford, East London, at 1.55pm on Wednesday. The Met Police has said between 10 to 15 people were injured in the crash.
TfL have confirmed the crash involved a 174 service, which runs from Dagnam Park Square to Marsh Way in Dagenham.
The Met Police have also encouraged all motorists to steer clear of Main Road in Romford following the crash.
A spokesman said: “Police are dealing with an incident reports of a bus in collision with an apartment block at Main Road, Romford.
‘Officers and London Ambulance Service [LAS] attended. Delays expected. Motorists are advised to avoid the area if possible.”
MORE TO FOLLOW