A 47-year-old cyclist who was knocked off his bike on Tuesday morning died from his injuries last night, police have confirmed.
The man was hit as he was riding along Warrington Road in Bold Heath at around 6.40am.
A 38-year-old man has been arrested on suspicion of causing death by dangerous driving.
Det Insp Simon Draco of St Helens CID said the force of the impact sent the victim flying into a nearby hedge.
Anyone with information can contact St Helens CID on 0151 777 6803, the Roads Policing Unit on 0151 777 5747 or Crimestoppers, anonymously, on 0800 555 111.