An Andy Warhol painting about civil rights protests in Alabama, US, in the 1960s has sold for $15.1m (£8.1m) - just short of a record for the artist.
Mustard Race Riot depicts police attacks on civil rights demonstrators
Mustard Race Riot, from 1963, depicts violence in Birmingham on one large panel, with a blank adjoining panel.
Christie's auction house in New York, where it was sold on Wednesday, said it was an "extremely rare and provocative" example of the artist's work.
Warhol's record is $17.3m (£10.6m) for a painting of Marilyn Monroe in 1998.
Mustard Race Riot sold as part of Christie's post-war and contemporary art auction, which raised a total of $92.5m (£50m) of art on Wednesday.
'Fast and furious'
Other high prices came for pieces by Cy Twombly, Alexander Calder and Roy Lichtenstein, with records set for Robert Motherwell and Maurizio Cattelan.
"From where I stood tonight, the bidding was fast and furious on almost every lot," said auctioneer Christopher Burge.
"We saw a number of records set this evening, which shows the continued vigour and energy in the market for fresh and compelling works."
Mustard Race Riot was inspired by three photographs of police attacks on civil rights demonstrators in May 1963 from Life magazine, which he recreated on one of the work's panels.
It is part of Warhol's Death and Disaster series, which is "considered to be one of the greatest artistic contributions to the 20th Century", Christie's said.
It was also the only overt political issue he tackled during his career, the auction house said.