“Many Arabs who seek freedom, equality and democracy feel defeated,” wrote the Saudi Arabian journalist Jamal Khashoggi in August. “They have been portrayed as traitors by pro-government media and abandoned by the international community.” Mr Khashoggi, who has written for the Guardian, is one such Arab. For more than three decades he has used his voice as a commentator, and position as an editor, to advocate for social and political reform in Saudi Arabia and the wider Middle East. Just over a year ago, in his first column for the Washington Post, he wrote of his anguish following a wave of arrests that included several of his friends – and explained that repression at home lay behind his decision to go into exile. This week Mr Khashoggi vanished in Istanbul, after entering the Saudi consulate there on Tuesday because he needed documents to marry his Turkish fiancee. The international community must call the Saudi authorities to account, demand proof that he left the consulate as they claim, and show that Mr Khashoggi has not been abandoned.

These are dark times for press freedom globally. The number of reporters imprisoned and killed has risen. The independence and diversity of the media in many countries is diminishing. New commercial pressures and the growth of the internet at the expense of news publishers are part of the explanation. So are the resurgence of authoritarian politics, and anti-democratic attacks on “fake news”. Turkey has seen some of the harshest repression, which intensified after the attempted coup against President Recep Tayyip Erdoğan in 2016, with titles closed down and many journalists put in prison.

Yet it is to the Turkish government that Mr Khashoggi’s supporters must turn in their efforts to locate him. Authorities in Istanbul have already summoned the Saudi ambassador over his case. The consulate is being watched closely. The fear is that Mr Khashoggi may already have been spirited away in a diplomatic vehicle and returned to Saudi Arabia. Numerous other commentators and intellectuals who have fallen foul of Prince Mohammed bin Salman are already in detention.

When he was promoted to heir by his father, King Salman, last year, the crown prince – sometimes styled MBS – declared himself a moderniser who wished to return the kingdom to a more moderate Islam and shift the economy away from its dependence on oil. Since then cinemas have opened, and women been allowed to drive. Some western observers had hoped he might be willing to introduce a degree of political reform. Instead, intolerance ramped up – with women who had campaigned for the right to drive among those jailed. MBS is no keener on criticism from overseas, lashing out at Canada when it criticised human rights abuses. That should not deter others from having their say now. Mr Khashoggi set his face against such intimidation. We admire his courage and stand by him.