A two-year-old boy has been killed in an accident involving an ambulance at a nursery school in Ealing, west London.
Oliver Ladwa, who lived locally, died during a visit by the London Ambulance Service (LAS) to St Barnabas Playgroup in Pitshanger Lane on Thursday morning.
Police and an air ambulance were called but the child, who was outside the vehicle at the time of the accident, died at the scene.
The ambulance is to undergo a detailed mechanical investigation, police said.
A statement from St Barnabas Playgroup said everyone was "shocked and greatly saddened following today's tragic events.
"All our thoughts are with the family at this distressing time.
"All parents with children at the playgroup have been informed and in light of today's events the playgroup will not be opening tomorrow."
Reports of a collision
Police were called at 1125 BST to reports of a collision involving an ambulance, outside St Barnabas Church Hall.
Air ambulance and other LAS units were sent to the scene, but the child was pronounced dead 30 minutes later.
An LAS spokesman said: "Our thoughts are with the child's family following this terrible tragedy.
"The police are investigating and we will obviously be co-operating fully with their inquiries."
A post-mortem examination is due to be carried out on Friday, said police.
St Barnabas Pre-school is independently managed and is run from a hall within the church.
It employs eight members of staff and can take up to 26 children at one time.