ROME, Aug. 9 (Xinhua) -- Sardinia, a tourist-packed Italian island, has some of the most beautiful beaches in Europe. But local authorities warned that they will become far less attractive if tourists keep stealing sand as souvenirs.

Sardinian authorities have decided to get tougher with "sand thieves" and are issuing fines of up to 3,000 euros (about 3,475 U.S. dollars). In the latest case, a British tourist has been fined 1,032 euros (about 1,195 dollars) for taking sand from a beach on the island.

"Sand theft," according to Italian media, has been troubling the Mediterranean island for years as some tourists make a habit of putting beach sand in plastic bottles despite beach signposts clearly warning that this is forbidden.

Customs officials at Sardinia's two airports regularly check tourists' luggage for consignments of sand. Last year around five tons of sand were intercepted.

Indignant islanders have formed vigilant groups to patrol the beaches. A few years ago, the residents set up a Facebook page called "Sardinia is being robbed and pillaged," which attracted about 20,000 likes.

Tourists may find Sardinian sand particularly tempting because of its variety: Some of the beaches boast sugary white sand while some others have sand of a distinctive pink hue due to a mix of fragments of coral, granite and shells.