William and Kate were traveling from London to Windsor on Monday when the incident took place on Upper Richmond Road in Richmond, BBC reported.
A spokesperson for Independent Office for Police Conduct explained to The Telegraph that a police motorcycle was involved in a collision with “a woman pedestrian.”
“The woman, in her 80s, suffered serious injuries and was taken to a London hospital where she remains in a serious but stable condition,” IOPC told The Telegraph.
At this time, the IOPC is investigating the incident.
“We are investigating the circumstances surrounding a collision involving a marked police motorcycle attached to the Royalty and Specialist Protection Command and a woman pedestrian on Upper Richmond Road, Richmond, south west London at 12:50 p.m. on Monday 17 June,” IOPC said to The Telegraph.
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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 has been identified as Irene Mayor, 83. Irene’s daughter Fiona told The Sun, that her mother has “got lots of injuries. They are just keeping her stable at the moment.”
Kate and William have since sent their well wishes to Irene.
“The Duke and Duchess of Cambridge were deeply concerned and saddened to hear about the accident on Monday afternoon,” a spokesperson for Kensington Palace said, BBC and The Telegraph reported.
“Their Royal Highnesses have sent their very best wishes to Irene and her family and will stay in touch throughout every stage of her recovery.”
On Monday, the couple was on their way to Windsor to attend one of the oldest royal traditions: Order of the Garter. The annual celebration of the Order of the Garter, one of the oldest and most senior order of knighthood in the U.K.