A 22-month-old girl in a pram has died after a collision with a car in north-west London.
Police were called shortly after 4pm on Sunday for reports of a collision with a car and three pedestrians in Eastcote Road, Ruislip.
The child was pronounced dead at the scene.
Another pedestrian, a man in his 30s, was taken to hospital and is in critical condition.
A man in his 40s has been arrested on suspicion of causing death by dangerous driving, causing serious injury while driving and driving under the influence of drugs.
He is currently in custody.
Met police officers – including some who were not on duty – and paramedics were on the scene.
The child’s family has been informed and they are supported by specially trained officials.
A post mortem is set to take place.
The police are now appealing for witnesses or someone else with dashcam or CCTV images to appear.
Detective Sergeant Sarah Donegan from the Met Police said: “Our thoughts are with the child’s parents at an unimaginably difficult time.
“We have launched an investigation to determine the circumstances of what happened and I ask anyone who was nearby at the time who may have seen something, or who has a film camera or CCTV, to come forward and help us with our investigation.”
Witnesses are asked to call 020 8246 9820 or 101 ref CAD 4892 / 25OCT20. You can also contact the independent charity Crimestoppers on 0800 555 111.