Tributes have been paid to a five-year-old boy who died after being in the back seat of a car that crashed with a motorcyclist at a junction.

A KTM motorcycle and a Ford Focus collided on the B4011 in Blackthorn near Bicester at the junction with Thame Road on Sunday (April 14) at around 2pm.

The rider of the motorbike, a man aged in his 40s, was taken to the John Radcliffe Hospital in Oxford with serious injuries.

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The driver of the Ford Focus, a woman in her 30s and a nine-year-old child, were also treated in hospital for less serious injuries.

Tributes have been paid from across the county in the Oxford Mail's book of condolence following the news.

Sophia Howie wrote: “My heart goes out to all the family and friends of this little boy who is only a year younger than my son.

“This really hit home for me. I am lost for words.”

Oxford Mail: The junction on the B4011 with Thame Road The junction on the B4011 with Thame Road (Image: Google Maps)Kerry Scotcher wrote: “I am truly so sorry for learning of this devastating news there are no words that can justify the loss of this little boy.”

Jamie, who did not provide his surname, added: “Sending the family and friends so much love. I cannot begin to feel your pain but I hope you feel the love and support. RIP little one.”

Another added: "There will never be words that will ease the pain at this time and words fail me right now.

"Nothing I say will ease that pain that the family are feeling but may god bless and take care of the family all at this dreadful time."

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While someone else said: "Absolutely heartbreaking, thinking of the poor family of this beautiful little boy."

Tracey Veal said: “Oh my word, what dreadful news. Our loving thoughts go out to his loved ones. Can’t imagine their sadness.”

Julie Mearns wrote: “Sending love to all of the family. What a waste of a young life taken way too soon.”

Carson Loveless wrote: “Condolences to his family and his loved ones.”

Becca Carver wrote: “My deepest sympathy and much love to the whole family.”

Oxford Mail: The John Radcliffe Hospital The John Radcliffe Hospital (Image: Oxford Mail)

No arrests have been made as Thames Valley Police has launched an appeal for witnesses following the incident.

The Oxford Mail has asked the force for an update on the condition of those in hospital as well as whether any arrests have been made.

Lead investigator Phil Hanham of the Serious Collision Investigation Unit, based in Bicester, said: “Very sadly, as a result of this collision, a child has died of his injuries.

"His family are being supported by specially trained family liaison officers and the thoughts of all of us at Thames Valley Police are with them at this extremely upsetting time.

“I would like to appeal to anybody who witnessed this collision to please get in touch with Thames Valley Police.

“I am particularly looking to hear from anyone who may have been driving in the area and who has dash-cam which has captured the collision, or the moments leading up to it, to please contact us.

Oxford Mail: Tributes have been left to the boy who died in our book of condolence Tributes have been left to the boy who died in our book of condolence (Image: Pixabay)

“You can do so by making a report online or by calling 101, quoting the reference 43240170525.

“I would like to thank those who stopped at the scene to offer assistance and those who have already got in touch with us.

“No arrests have been made and our investigation is in its very early stages, so please do get in touch if you have any information that can assist the investigation.”