On his way to board a flight to Doha at Haneda airport in Tokyo this past Saturday night, Kosuke Tsuneoka's passage was abruptly halted.

What derailed his plan was something he has since said he had not expected at all: his home country.

The freelance journalist's final destination was Yemen, a country experts have described as facing the worst humanitarian crisis in the world. At immigration control, an officer told Tsuneoka that his passport had been invalidated and that he was ordered by the government to relinquish it — in effect banning him from leaving the country.