Police are appealing for witnesses to the incident to come forward
Police are trying to establish whether a boy critically injured after coming off his bicycle was involved in a collision with another vehicle.
The 10-year-old was taken to Ysbyty Glan Clwyd hospital in Bodelwyddan with head and chest injuries after the incident at Llanrwst, in Conwy county.
He was later transferred to Alder Hey Hospital in Liverpool.
North Wales Police said the incident took place on the A470 at Llanrwst near the Central garage on Monday afternoon.
The road was closed after the incident, which was reported at 1618 BST, and diversions were put in place.
Police are continuing to investigate and are appealing for witnesses to come forward.
Anyone with information is asked to contact the western roads policing unit on 0845 607 1002 (English line) or 0845 607 1001 (Welsh line).