With nearly 400 unmanned aerial vehicle (UAV) manufacturers, China now makes up approximately 70 percent of the international drone market.

According to the city’s customs bureau, drone exports out of Shenzhen increased seven times in 2015 over the year before, totalling 3.09 billion yuan ($472 million) in sales.

Approximately 43 percent of these exports pass through Hong Kong before being shipped to markets in North America and Europe. Another 18 percent are shipped directly to the USA.

In August 2015, China banned certain drone exports, citing “threats to national security”. Drones capable of flying at an altitude of 15,420 meters, with a flight duration over an hour, were listed as illegal exports by the Ministry of Commerce and the General Administration of Customs. The ban was announced two weeks after a Chinese-made drone was shot down between the India-Pakistan border.

Chinese airspace is highly regulated and tightly controlled by the Chinese military, which cracked down on the civilian use of drones last November.

Although 99 percent of Shenzhen-made drones are exported to foreign markets, a leading drone manufacturer, DJI, recently opened its flagship store in the city to sell to local buyers.

Despite the restrictions, there is a growing cottage industry of drone pilot schools in China. Trained and licensed, these certified drone pilots can earn a monthly salary up to 5,000 yuan ($780), exceeding the national average in fields such as agriculture, film production, and law enforcement.

Chinese online retailing giant, JD.com, announced it would start test drone flights to make deliveries in rural areas of China. Rival Alibaba had previously conducted a promotion using drones to deliver packages of tea last year.