Jamal Khashoggi hasn't been seen since last week

The US president Donald Trump says "rogue killers" could be behind the disappearance of a Saudi journalist.

Jamal Khashoggi was a critic of Saudi Arabia's crown prince - he hasn't been seen since going into the country's consulate in Istanbul two weeks ago.

Turkish authorities believe he was murdered.

The U.S. Secretary of State's arriving in Saudi Arabia to meet with King Salman - who's previously denied involvement in the case.

There's speculation Saudi officials may be preparing to admit he was killed during a botched investigation.