A woman is in "critical condition" after being struck by a motorcycle in Cricklewood.
Police were called at about 3.35pm on Thursday - July 7 - to reports of a collision on Chichele Road, at the junction with Melrose Avenue.
Officers attended alongside London's Air Ambulance and the London Ambulance Service.
The injured pedestrian - a 39-year-old woman - was taken to hospital where she remains in a critical condition.
Police arrested the rider of the motorcycle on suspicion of driving while under the influence of drugs.
After receiving hospital treatment he was taken to a north London police station where he was subsequently released under investigation while enquiries continue.
Detectives from the serious collision investigation unit (SCIU) are investigating.
They are particularly keen to hear from any witnesses who saw the collision, or captured it on dash cam or CCTV.
Any witnesses yet to speak with police are asked to call the SCIU on 020 8246 9855 or via 101 quoting reference CAD 4799/07Jul.
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