A 35-year-old woman was seriously injured when she was hit by a stolen motorbike in Birmingham.
The crash happened just before 15:00 BST, West Midlands Police said. Officers were called after a man was threatened with a knife and had his motorbike stolen outside Bristol Street Motors near the city centre.
The Yamaha bike later hit the woman on Bristol Road, the force said.
The bike was later recovered, but the suspects had fled the scene.
The force said it was believed two men escaped on a bicycle.
Bristol Street was closed, West Midlands Police said.
The force appealed for witnesses to come forward.
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