Scotland Yard told NBC News that a police motorcycle was "involved in a collision with a pedestrian. The woman, believed to be in her 80s, has been taken to hospital for treatment where she remains."
The woman's injuries were described as "serious" by the Independent Office for Police Conduct, which is investigating the incident.
"In line with procedure, the Metropolitan Police Service referred the collision to the IOPC," the IOPC told NBC News. "Our staff attended the scene of the incident and after careful consideration, we have launched an independent investigation. The investigation is in its very early stages and the officer involved is assisting our enquiries as a witness. Our immediate thoughts are with the injured woman and her family and those affected by the incident."
A spokesperson for the royal couple said Prince William and Duchess of Cambridge did not see the accident.
A witness told The Sun, "His bike hit her and she spun round, off her feet and fell badly on the floor."
The injured woman was identified as Irene Mayor, 83. Mayor's daughter, Fiona, told The Sun that her mother "got lots of injuries. They are just keeping her stable at the moment."
"The Duke and Duchess of Cambridge were deeply concerned and saddened to hear about the accident on Monday afternoon," a palace spokesperson said. "Their Royal Highnesses have sent their very best wishes to Irene and her family and will stay in touch throughout every step of her recovery."
A member of the couple's staff reportedly visited the woman and delivered flowers, while Hello Magazine reports that the couple requested to visit Mayor if she is up to it.
William and Middleton were traveling from London to Windsor on Monday when the incident took place on Upper Richmond Road in Richmond, BBC reported. The couple was on their way to attend the Order of the Garter, one of the oldest royal traditions that celebrates one of the oldest ad most senior order of knighthood in the U.K.0comments
The couple followed it up on Tuesday with an appearance at the Royal Ascot.
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