As multimillion-pound art heists go, it's on a par with the Thomas Crown Affair. There was no shoot-out or dramatic getaway, broken windows or forced doors: not so much as a motion sensor was disturbed when thieves entered a Los Angeles mansion and stole a series of Andy Warhol prints depicting famous sports stars including Muhammad Ali, Chris Evert and Pelé.
"This was a very clean crime. For some reason they had an interest in this collection," Detective Mark Sommer of the Los Angeles Police Department admitted yesterday. One reason might be its value – one of the Ali prints recently sold for $9m (£5.5m). Faced with something of a blank canvas, the LAPD is now offering a $1m reward for the return of the 11 silk-screen paintings, whose bold colours and distinctive style instantly mark them out as the work of the legendary American artist.
The pictures vanished from the home of the wealthy investment banker turned art collector Richard Weisman, who commissioned Warhol to create the pictures because he was looking for a way to merge the art and sports worlds. "I picked out the athletes," said Weisman, "because he didn't know the difference between a football and a golf ball."
Detectives investigating the art loss admitted that there was no sign of forced entry at the mansion. They said the theft was discovered 10 days ago by a domestic servant who noticed the paintings were missing. Ten of the 40in x 40in portraits feature sports stars. The 11th features Mr Weisman himself, who wrote a book, From Picasso to Pop, about his art collection.
"Richard is devastated," said the fine art dealer Martin Summers, a friend. "He had other paintings, including Warhols, in the house, and doesn't understand why they took the 'Athletes' series and left them."
Two years ago a set of the 'Athletes' prints – of which Warhol originally produced eight – was exhibited and offered for sale at a guide price of $20m- $30m by Mr Weisman at Martin Summers' gallery, but failed to find a buyer.
"Just last week I got a call from a buyer in China asking if they were still for sale, and then when I called Richard to talk to him about it he told me they'd been stolen," Mr Summers said.
The crime is being investigated by the LAPD's art theft team. The unit, the only such dedicated team in the US, has recovered around $80m worth of art since 1993. "There is a public misconception that art crime is perpetrated by gentlemen, but actually most art crime is done by organised crime syndicates involved in drugs and terror," said Terressa Davis, director of the Association for Research into Crimes against Art. "Very occasionally, specific paintings are stolen to order, but more often they are held to ransom, or used as collateral by criminals trading with other criminals."