Treasure hunters have swarmed to the South China Sea in great number in recent years, seeking to uncover the region's massive quantities of underwater relics. However, their actions have also endangered the region's cultural heritage, prompting authorities to take action.

China's Xisha Islands, also known as the Paracel Islands, occupy an area of 15,000 square km in the South China Sea. Speculators and local fishermen have been surveying the waters around the islands for treasure since 1996, when a local fisherman discovered an ancient shipwreck in the area.

Many of the hunters use crude means to retrieve underwater relics, lacking both proper equipment and government approval. Destructive looting has done irreversible damage to the shipwrecks of the Xisha Islands.

XISHA ISLANDS: SUNKEN TREASURE CHEST

Lying on the route of the ancient maritime Silk Road, the waters around the Xisha Islands were and still are heavily traveled shipping lanes, with ships transporting goods between China and other countries in the Asia-Pacific region.

However, the waters around the islands are also known for their poor navigability, as they are surrounded by coral reefs. Historical records show that a number of ships struck hidden reefs and sank near the islands, taking their treasures with them to the ocean floor.

Official archaeological surveys show that there are at least 122 wrecked ships on the bottom of the South China Sea. Many of them date back to the Tang (618-907) and Song (960-1276) dynasties, when trade with foreign countries was thriving.