BEIJING, Sept. 24 (Xinhua) -- Authorities have banned 219 people from buying duty-free products in south China's Hainan Province for three years, the General Administration of Customs said Thursday.

Among the barred individuals, 28 received the punishment because they did not leave the island with duty-free products in accordance with regulations, while the rest were involved in selling duty-free goods for profits.

Starting July 1, Hainan has increased its annual tax-free shopping quota from 30,000 yuan (about 4,411.76 U.S. dollars) to 100,000 yuan per person. The categories of duty-free goods have also been expanded from 38 to 45, with products such as mobile phones and laptops added to the list.

Some people were found to have taken undue advantage of the new policy for profiteering, the administration said, adding that Customs will continue to strengthen supervision and crack down on market violations.