The Melbourne museum said the theft of the $202,000 painting, Low Tide at Boulogne, was not reported earlier because officials believed it may have been misplaced, The Daily Telegraph, Britain, reported Wednesday.
The painting, believed to have been created in 1824, is thought to have gone missing in 1999 when the 65,000 works possessed by the museum were temporarily relocated for renovations.
The artwork has now been reported stolen and listed on the International Art Loss Register.
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