Japan's government is scheduled to improve its nationwide J-ALERT emergency warning system to warn citizens of North Korean missile launches.

North Korea fired ballistic missiles in October and November. But the alert in November was issued after the time the missile was expected to fly over Japan.

To address the issue, the government plans to widen alert coverage areas by combining neighboring municipalities.

Currently, alerts are put out by prefecture, but officials say this requires too much time for analyzing information to narrow down target areas.

Officials say the change is expected to speed up alert announcements by about 1 minute, compared to the time it took to sound an alert in October.

They also say the upgrade should take about six months. The government aims to start operating the improved system around next summer.