Japan’s national broadcaster NHK has issued an apology after sending out a false alert claiming North Korea had launched a ballistic missile.

The alert, sent out shortly before 7pm local time on Tuesday, read: “North Korea appears to have launched a missile ... The government urges people to take shelter inside buildings or underground.”

The same alert was sent to mobile phone users of NHK’s online news distribution service, but was retracted within a few minutes.

​NHK apologised for the error on air, adding the “news alert sent earlier about NK missile was a mistake. No government J alert was issued.”

The message was sent out just days after an emergency missile text-message alert was accidentally sent to residents in Hawaii, sparking mass panic.

Residents and holidaymakers in Hawaii awoke to a message which read: “Ballistic missile threat inbound to Hawaii. Seek immediate shelter. This is not a drill.”

It was transmitted to mobile phones and broadcast on television and radio across the island shortly after 8am local time on Saturday.

A second alert clarifying there was no missile threat did not come until 38 minutes after the initial false alarm.

The mistake unleashed hysteria across Hawaii as many feared the worst.

A spokesperson for Hawaii’s emergency management agency later said an employee mistakenly pressed the “wrong button” during a routine drill.

Spokesperson Richard Rapoza said the unnamed employee, who has been relocated, made the wrong selection from a “drop-down” computer menu, choosing to activate a missile launch warning instead of the option for generating an internal test alert.