Pictures snapped by an 18-year-old photographer at The Beatles' first US concert have sold for £225,000.
The 50 silver gelatin prints all sold individually and had been estimated to make \$100,000 (£62,000).
Photographer Mike Mitchell took the snaps at the Washington Coliseum on February 11, 1964, two days after their debut on The Ed Sullivan Show on television.
Among the highlights is a backlit shot of the band that he took while standing directly behind them.
It sold for \$68,500 (£42,500), although it was expected to fetch less than \$3,000 (£1,800).
Cathy Elkies, Christie's director of iconic collections, said she expected the bids to exceed the pre-sale estimates.
"Beatles fans are fierce. To uncover this trove of images that's never been published will really excite people," she said.
In a recent interview, Mitchell described the rollicking scene at the Washington indoor arena not only of screaming fans but also of his unrestricted access.
"It was a long time ago. Things were that way then," said the 65-year-old, who now works as an art photographer in Washington.
"It was as low-tech as the concert itself. The concert was in a sports venue and the sound system was the sound system of a sports venue."
Mitchell stored the negatives for years in a box in his basement.
He used digital technology to scan and restore the prints for the auction.