A work of art that has been described as "the Mona Lisa of sculptures" has been stolen from Vienna's art history museum.
The glass case containing Cellini's Saliera was smashed
The 16th Century solid gold sculpture by Benvenuto Cellini was worth at least 50m euros ($57m, £36m), museum director Wilfried Seipel said.
Police believe the work, called Saliera, or salt cellar, was stolen to order because it was the only piece taken.
"This is an art theft of gigantic proportions," Mr Seipel told Austrian television.
The museum said Cellini's piece was the sculpture equivalent of Leonardo da Vinci's 16th Century masterpiece painting the Mona Lisa.
Thieves stole the sculpture from its glass display case after smashing a window to get into the museum, police said.
"The thieves climbed up some scaffolding to the first floor of the building, broke a window and climbed in," a police spokesman said.
We are currently investigating why the alarm did not go off
"They shattered the glass display case and took the sculpture."
"There were movement sensors all over the place - we are currently investigating why the alarm did not go off."
Saliera, which is 26 centimetres (10 inches) tall, is Cellini's only remaining authenticated gold work.
'Impossible to sell'
It depicts a male figure representing the sea and a female figure that represents the earth.
The theft was discovered on Sunday. Mr Seipel said the sculpture was insured against theft.
It was impossible to sell on the regular art market, he said.
Police have notified Interpol and said they would work with British, German and
Italian authorities to try to track the sculpture down.