An 11-year-old boy has been taken to hospital in a critical condition after being hit by a police van, Lancashire Police have said.
The force said the incident occurred on Owen Road, Lancaster just before 20:30 BST as officers were responding to an emergency call.
It said the boy, who was crossing the road at the time, has been taken to the Royal Lancaster Infirmary.
The road has been closed and is expected to remain so for some time.
Lancashire Police said an investigation is underway and that it had referred the matter to the Independent Office for Police Conduct (IOPC), "as is standard with an incident of this nature".
"Our thoughts are with the child's loved ones at this time," it said.
A spokesperson for the IOPC said it had been notified of the collision shortly after it occurred and that investigators were gathering information.
"We understand that a marked police van, with its lights and sirens on, was in a collision with an 11-year-old boy," they said.
"He has been taken to hospital and our thoughts are with him and his family.
"Our investigation is at an early stage."
Anyone with any information or who has any CCTV or dashcam footage that may assist the investigation is being asked to call 101 and quote log 1388 of May 25.
