Three defendants in China's first case of the illegal use of unmanned aerial vehicles have been sentenced to 1 and a half year prison terms, as well as imposing two years' probation, in Beijing.

Prosecutors charged the three defendants for crimes of negligently endangering public security through dangerous means.

The defendants' illegal use of unmanned aerial vehicles caused emergency avoidance and delay of several civil aircrafts.

It was the first case involving unmanned aerial vehicles here in China.

Unmanned aerial vehicles have been adopted in wide use in civil areas in recent years across China, in agriculture, and industries such as the power sector.

However according to senior aviation expert Zhang Qihuai, more legal regulations and supervisions policies are in urgent need of the unmanned aerial vehicle industry.

"Till now, China's civil aviation law is lagging behind, as it has not been revised for 15 years. Some industry regulations are also falling behind. Especially about the unmanned aerial vehicles, a regulation has just come out to the teaching staff of using the vehicle, but other rules are still blank currently. So China's legislators and civil aviation authorities should strengthen and improve the legislation. "

Statistics show that more than 170 companies now produce unmanned aerial vehicles in China, and the market value is expected to reach more than a hundred billion in the coming years.