BEIJING -- China will cover key public areas with video surveillance by 2020 to combat crime and improve public service, the country's top economic planner said Wednesday.

Public areas such as roads will be fully covered by cameras and their surveillance information will be shared among authorities, according to a guideline released by the National Development and Reform Commission and eight other departments.

The plan aims to enhance public security monitoring, optimize traffic conditions and improve social management.

Local governments are required to make sure most of the surveillance cameras can function effectively around the clock and build a multi-tier public security surveillance system.