A 15-year-old girl was killed when the motorbike she was riding on was involved in a crash with two other vehicles.
Thames Valley Police said a collision occurred between a white Toyota Yaris, a grey Toyota Hilux and a motorbike on the A355 in Buckinghamshire at roughly 9.20pm on Friday.
The driver of the motorbike, a 16-year-old boy, has been arrested on suspicion of causing death by dangerous driving.
A 16-year-old boy and a 15-year-old girl from High Wycombe, who were travelling on a separate motorbike, have also been held on suspicion of causing death by dangerous driving.
The force said a mandatory referral has been made to the Independent Office for Police Conduct (IOPC) as a police vehicle was nearby.
The police vehicle was driving on the opposite carriageway, not on blue lights, it said.
Lead investigating officer Oliver Cahill-Smith said: "Firstly, I would like to share my sincere condolences with the family of the girl who has sadly died as a result of this collision.
"I am appealing to anyone who witnessed the incident to please get in touch.
"I would also like to ask anyone who was driving in the area prior to the collision to review their dash-cam footage as it may contain information that could assist our investigation."
(c) Sky News 2026: Girl, 15, killed in motorbike crash with boy arrested
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