A honey-making company lost £100,000 of business after two million bees were destroyed in a suspected Mafia hit.
Raiders wearing protective masks are thought to have struck at night, spraying more than a dozen hives with insecticide.
Police in Titignano, Italy said: "We're working with the owner of the apiary to see if he's been the victim of threats or extortion from crime gangs."
The specialist bee farm houses prize bees used to make the Italian Millefiori brand of honey.
Police said the gang used wire cutters to get through a fence during the night.
Owner Sergio D'Agostino said: "I've no idea why anyone would want to do something like this.
"I've lost more than two million bees and the financial cost will be huge - we are talking tens of thousands of Euros.
"This is the prime time for the bees and whoever did this knew what they were doing. It's going to take me months to get back to where I was before this attack.
"They used a powerful insecticide which you can buy in any shop and just took the hives out. It is a slaughter and they came at night so they could not be seen.
"Each hive is worth around 400 Euros, then you have the bees on top and we were due to have a new and we were due to get new clusters in shortly - that will have to be cancelled now."
A police spokesman said: "This was obviously carried out by a gang of people who knew what they were doing. They used powerful insecticide and we suspect they were probably wearing protective suits.
"We have asked local hospitals to let us know if anyone comes in with multiple stings but so far there have been no reports. The possibility this was an operation linked to organised crime has also not been ruled out.
"We are working closely with the owner of the apiary to see if he has been the victim of threats or extortion in the past from organised crime gangs.
"It is a business operation which makes a considerable amount of money and they have now suffered financially as a result."