Japan plans to double the number of its intelligence-gathering satellites in operation to eight from the current four from fiscal 2023 onward to bolster its surveillance network, deemed as having a de facto spy purpose, officials said.

The current setup is already capable of collecting images of any point on the ground at least once a day. But the Cabinet Satellite Intelligence Center envisions increasing this ability further, the officials said Wednesday.

Japan has three optical satellites suitable for shooting in daytime and three radar satellites that can be used at night or in bad weather. Four of the six are usually in operation, while another is for standby and the remaining one has exceeded its operational life span.

The center plans to launch the first of the satellites under the new scheme around fiscal 2023, with development to start from next fiscal year starting in April, the officials added.

The center expects the new system will make it possible to grasp in detail such activities as the movement of suspicious vehicles or construction work, they said.

Images captured by the satellites are designated as state secrets under a secrecy law that took effect last year.