Jessica Ennis has sent her best wishes following his bike crash.
The Olympic heptathlon gold medallist told Channel 5 News: "I saw the news this morning and obviously I just want to wish him well. Hopefully he'll make a speedy recovery and gets back on his bike.
"It is very dangerous and you hear about some horrible accidents, and stories about what happens to cyclists, and I know he's been campaigning about road safety, so it's awful that's happened to him but hopefully he can recover quickly and get back to it."
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Five people were killed and dozens more were injured after a car and knife attack in the capital on Wednesday afternoon.
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Five people have been killed and 40 injured after a car and knife attack in London on Wednesday.