31 March 2018
On 31 March, China launched three Gaofen-1 imaging satellites as part of the country's high-definition Earth observation project. The satellites was launched off on the back of a Long March 4C rocket at 11:22 a.m. Beijing time from the Taiyuan Satellite Launch Center in northern Shanxi Province. It was the 270th flight mission by a Long March carrier rocket.
MORE...

video: China puts 1st commercial satellite constellation into use - Mission profile

The launch of three Gaofen-1 high-definition imaging satellites marks the beginning of China's efforts to build a national civil space infrastructure system scheduled to be completed in 2025.
CCTV video footage of the launch, launch preparation and interviews with space officials

China released many videos on the launch and the mission of the Gaofen satellite triplet. Follow the link for more videos.