A father saw his 12-year-old son fatally injured when the boy was involved in a crash with a white van as the two rode together on a country road.
The child suffered critical injuries in the lunchtime incident on Saturday and lost his fight for life today when he died in hospital.
The smash happened on the B471 Whitchurch Hill near Pangbourne, Berks.
The driver of the van stopped at the scene and there have been no arrests.
A spokesman for Thames Valley Police said that the young boy had not yet been named but his family was being supported by specially trained liaison offices.
“At around 12.55pm on Saturday a boy was cycling along the B471, Whitchurch Hill, heading towards Pangbourne, when he was in a collision with a white van, which was heading up Whitchurch Hill towards Crays Pond.
“The 12-year-old boy sustained serious injuries and sadly died in hospital today. His family are now been supported by specially trained officers.
“The driver of the van remained at the scene and no arrests have been made.”
Senior Investigating officer Sergeant Darren Brown, of the Serious Collision Investigation Unit at Three Mile Cross, said: “At the time the boy was cycling with his father. If you think you saw them around this area we would like to speak you.
“We would also like to speak to anyone who saw the incident or the white Volkswagen Crafter van which was involved in the collision. This is a rural location but we hope someone may have some information to assist with our investigation and may have seen something.
“If you have dash-cam or CCTV in the area, we would ask you check this and please share anything significant with us. You can contact us by either calling 101 or making a report online.”
A post mortem examination is to be carried out on the child’s body to ascertain the exact cause of his death and an inquest will be opened and adjourned later in the week.