A three-year-old boy is being treated in hospital after he was hit by an ambulance responding to a call.
The emergency vehicle collided with the child in Horsham Road, Littlehampton, on Thursday morning.
A South East Coast Ambulance Service NHS Foundation Trust (SECAmb) spokesman said: "SECAmb can confirm that it has responded this morning to reports one of its ambulances had hit a child on Horsham Road, Littlehampton, at approximately 10.40am.
"The child, a three-year-old boy, is not believed to have suffered serious injuries but has been assessed and treated before being taken to Worthing Hospital for further checks.
"The vehicle was responding to a call at the time and we are working with police to establish the circumstances.
"Our thoughts are with everyone involved who are obviously extremely distressed and we are liaising closely with the child's family."
The spokesman said that the investigation would look at whether the ambulance had its blue lights and sirens on at the time of the accident.
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