China has set up its first "commercial" quantum network in the northern province of Shandong, its latest step in advancing a technology expected to enable hack-proof communications.
China says it is at the forefront of developing quantum technology. In August it sent its first "unbreakable" quantum code from an experimental satellite launched a year earlier. The Pentagon has called the satellite a "notable advance."
Now the country's "first commercial quantum private communication network" has been set up for exclusive use by more than 200 government and official users in Shandong's provincial capital, Jinan, the official Xinhua News Agency said late on Tuesday.
It did not elaborate on how the system would be commercially operated.
"Hundreds of pieces of equipment connected by hundreds of kilometers of fiber optics were installed within five months," Xinhua said.
The network provides secure telephone and data communication services and is expected to be connected to a Beijing-Shanghai quantum network, the news agency said.
Quantum channels send messages embedded in light; attempts to disrupt or eavesdrop on them create detectable disturbances.
Other countries, including the United States, have been working on their own quantum networks for years.