Japanese government officials withdrew a warning given on Thursday morning that asked people in northern Japan to take shelter.
The alert came after North Korea fired what appeared to be at least one ballistic missile toward the Sea of Japan.
Officials canceled the warning half an hour later.

The Defense Ministry says North Korea fired a suspected ICBM-class missile at around 7:22 a.m. on Thursday.
It says it did not appear to fall or fly through Japan's exclusive economic zone.

South Korea's military says it was launched from near Pyongyang, and was an intermediate or longer-range ballistic missile that flew about 1,000 kilometers. It is the 12th time this year that the North has conducted a launch.
The launch triggered what is called a J-Alert warning across the country for the first time since last autumn.
But there are concerns about its accuracy after it sent out false alarms last October and November.

Chief Cabinet Secretary defended Thursday's warning, saying it was not a misjudgment because officials believed it was a threat to public safety. Matsuno Hirokazu said at a news conference, "I think it was appropriate to have activated the J-ALERT warning for this particular incident, considering the role that it was supposed to play."

Some politicians are calling for the government to look into possible problems with the J-Alert system.