The incident happened at the junction of Church Street and Siviter Way just after 10.45am today (December 2).
Officers and London Ambulance Service crews attended and found a woman injured.
She was treated at the scene before being taken to hospital where her condition is unknown.
We have contacted Metropolitan Police for further details.
A spokesperson for London Ambulance Service said: “We were called at 10.47am today (2 December) to reports of a road traffic collision at the junction of Church Street and Siviter Way, Dagenham.
“We sent an ambulance crew, a paramedic in a fast response car and an incident response officer to the scene.
“We treated a patient at the scene and took her to a major trauma centre as a priority.”