TODAY staff and wire reports:
The couple waved to the hundreds of spectators before walking up the steps of Old Marylebone Town Hall for the ceremony.
Shevell was wearing a white dress designed by McCartney's daughter Stella as she and McCartney arrived at the town hall.
The couple announced their engagement earlier this year. Shevell, 51, would be McCartney's third wife, and it would be her second marriage.
The 69-year-old McCartney married his first wife, Linda, at the same venue in 1969. She died of cancer in 1998. His 2002 marriage to model Heather Mills collapsed shortly after, ending in divorce in 2008.
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