Two drones were being used to help monitor traffic flow and violators on highways in China's Sichuan province, authorities said on Sunday.

The drones flew over two highways, one connecting the cities of Chengdu and Zigong, and the other connecting Chengdu with Mianyang, according to the provincial public security department.

More than 90 traffic incidents were caught on drone camera, Xinhua news agency reported.

The drones can recognize license plates from 100 meters away. The pictures and videos can be sent back to ground staff so the police can take efficient measures to direct traffic flow.

With a flight radius of 15 km, the drones can fly for up to one hour at a time, and can complete a 30 km round trip in 40 minutes.

The drones' activity was broadcasted live through the provincial traffic police's official social media account Weibo.

The traffic police will now use drones more regularly, the department added.