Members of Japan's Self-Defense Forces and the US military have held a competition to test their skills in coping with cyberattacks.
Twelve teams of experts from the Ground Self-Defense Force, the US Army Cyber School and others took part in the online competition.
The participants competed to see how quickly and accurately they could analyze networks and break codes.
Cyberattacks in the military field are often intended to disrupt command systems.
Improving Japan's capabilities to counter cyberattacks is cited as a major security challenge in the national defense program guidelines.
In the last fiscal year, Japan's Defense Ministry increased the members of the Cyber Defense Group, which was established in 2014. Cyber-security training of SDF personnel is also underway.
The SDF asked the US forces to hold the competition. SDF officials say they hope to promote cyber-defense cooperation with the US forces, which are more advanced in this area.
A senior official of the Ground Staff Office, Jiro Hiroe, says there's a lot to learn from the contest. He says he hopes the event will help review bilateral cooperation and the SDF's training programs.