Japanese public broadcaster NHK has said an erroneous alert warning of a North Korean missile fired at Japan was sent by a staff member who meant to file a different newsflash.
NHK denied any mechanical flaw and said on Wednesday that it is studying preventive measures.
The erroneous newsflash on Tuesday said North Korea appeared to have fired a missile at Japan and that the government was warning people to take shelter.
NHK retracted the mistake within minutes and apologised on air and on other formats.
NHK is not sure how many of its 300,000 social media followers saw the alert or notification and it is unknown if anyone followed the instructions.
Days earlier, Hawaii’s emergency authorities sent a mistaken warning of a missile attack to mobile phones across the state, triggering panic.