SHANGHAI - Shanghai police have launched a daily air inspection on the traffic condition of three major highways since Sunday, according to the Shanghai Municipal Public Security Bureau.

The inspection would be conducted by helicopters for four hours a day over the highways that respectively link Beijing and Shanghai, Shanghai and Kunming, as well as Shenyang and Haikou, said a spokesman with the bureau.

The move was aimed at detecting congestion and providing real-time traffic information to citizens, as well as capturing traffic-violating behaviors as early as possibly, said the spokesman.

Since late March, similar air inspections have been launched on the city's main roads in rush hours of every Monday and Friday.