Chinese marine authorities began drone patrols for the first time over water and islands in the East China Sea close to North Korea last week.
Liaoning's marine department said it had set up an unmanned aerial vehicles (UAV) deployment and control centre in the coastal city of Dalian and would send drones on frequent missions to monitor sensitive ocean, coastline and island regions facing North Korea, gathering remote sensing data and high-definition photos.
Professor Li Ziwei, a researcher at the Chinese Academy of Sciences' Institute of Remote Sensing Applications who has participated in military drone projects, said the Liaoning scheme was run by the civilian government without the use of military-grade equipment. She warned that unless operated carefully, the drones may easily fly into other countries' territory and cause disputes.
'Civilian UAVs face very strict regulations on the mainland and therefore can only fly in some remote regions such as over oceans,' she said. 'But once out at sea they could easily turn up on the radar screens of another country's air force and increase the risk of diplomatic disputes.
'The operation looks dangerous.'
Chinese fishermen operating in the East China Sea have often been arrested and fined by South Korean marine authorities, while Chinese officials are keen to upgrade marine patrols in case of a sudden flow of refugees from North Korea.
Li said the drones used by the People's Liberation Army were among the best in the world, able to climb tens of thousands of metres and stay in the air for almost 24 hours without refuelling. But she said the model being used by the Liaoning authorities - with a camera only able to pick out objects no smaller than 50cm - almost certainly came from the civilian sector: 'Military UAVs wouldn't be used for daily tasks such as border patrols - they're too expensive.'
The Liaoning marine authorities said the drones would patrol 150,000 square kilometres of water, with more than 500 islands and islets.