BEIJING - China has collected detailed topographic information and images of all its islands using aerial remote sensing, a method allowing the capture of data about objects from a distance.

The completion of the project marks the country's first "systematic and comprehensive" move to collect surveillance information on the more than 10,500 islands within its territory, said the State Oceanic Administration (SOA) on Friday.

It took three years of work by the aviation law enforcement forces with the China Marine Surveillance (CMS), according to an SOA statement.

The administration said that the landmasses covered are on the official catalogue of China's islands, but none fall within the country's recently established Air Defense Identification Zone.

An islands surveillance plan mapped out by the SOA in 2011 required the CMS to conduct remote sensing and collect data on all reachable islands every three years, and said that such efforts should focus on islands listed for development, rehabilitation and protection.

According to the CMS, it will cooperate with the SOA island management department and the National Marine Data & Information Service in drafting an information sharing mechanism in order to strengthen technological support for the country's law enforcement work concerning its islands.