Four cyclists have been seriously injured in a crash with a car in Lincolnshire.
They were in collision with a VW Scirocco on the A15 at Ashby De La Launde at 02:25 BST on Sunday.
Police said the riders were part of a large organised bike ride, involving cyclists from across the UK, travelling to Sleaford.
A 29-year-old man was arrested shortly after the crash and remains in custody.
Lincolnshire Police would not confirm what he had been arrested on suspicion of.
A spokesman for the force said they could not release further details about the riders or the event they were taking part in until the family of the injured cyclists had been informed.