A teenager from Essex is in custody following a bus crash which left a 90-year-old passenger fighting for his life.
Police say a cyclist swerved into the path of the bus near Chelmsford town centre on Saturday.
The driver was forced to make an emergency stop and the elderly passenger was flung to the floor causing life-threatening head injuries.
The cyclist abandoned his damaged bike and left the scene before police arrived.
An 18-year-old has been arrested on suspicion of assault and dangerous cycling.