According to Kyodo News, Inada was visiting a base near the Nerima district in Tokyo.
Earlier in the day, the country's Defense Ministry said that the North Korean authorities had fired three ballistic missiles from Hwangju county in the direction of the Sea of Japan.
North Korea is currently under pressure from the international community since its January nuclear test and a long-range rocket launch in February, which resulted in the tightening of sanctions against Pyongyang in the new UN Security Council resolution in March.
On August 3, North Korea launched two missiles. One of them exploded immediately after launch, while the other one flew over the country's territory and fell in the Sea of Japan.