By Roland Buerk
BBC News, Tokyo
More than 2m bees were stolen last year, says Japan's apiary association
Japanese bee-keepers have been warned to be on their guard, following a spate of hive thefts.
The price of honeybees has doubled in recent years after a ban on imports. Police suspect a gang of specialist thieves is stealing honeybees to order.
In central Shizuoka prefecture, eight hives of 60,000 bees were taken in a single night from five separate farms.
The area is well known for strawberry growing and farmers need honeybees to pollinate their crops.
The insects have been in short supply in Japan after imports were banned for several years to try to prevent the spread of parasites.
The price of a swarm has doubled to more than $400 (£260).
The Japan Beekeepers and Honey Association says more than two million of the insects were stolen in 2009, and thefts are becoming more frequent.
The organisation has urged its members to be alert, but has admitted it is difficult to protect hives around the clock on remote farms.