SAUDI prosecutors say the killing of journalist Jamal Khashoggi was a premeditated crime.

Saudi Attorney-General Saud al-Mojeb said that investigators came to that conclusion after evidence presented by Turkish officials as part of the two nations’ probe into the killing.

Khashoggi was killed on October 2 at the Saudi Consulate in Istanbul.

Saudi Arabia had insisted for weeks that the journalist walked out of the consulate, before changing their account to say he died in a brawl.

It came as Human Rights Watch said Khashoggi’s son has left Saudi Arabia and is on his way to the United States.

Sarah Leah Whitson, the executive director of Human Right’s Watch’s Middle East and North Africa division, said that Salah Khashoggi and his family left the Saudi capital of Riyadh on Thursday after a travel ban on him was lifted.

A member of Saudi Crown Prince Mohammed bin Salman’s entourage on foreign trips was seen at the consulate before the Washington Post columnist’s death.

Meanwhile, the crown prince has attended the first meeting of a committee aiming to restructure the kingdom’s intelligence services after the killing of Mr Khashoggi.

The kingdom announced over the weekend that 18 Saudis had been arrested over the killing while four senior intelligence officials and an adviser to the crown prince have been fired.

On Wednesday, the prince called the killing “heinous” and “painful to all Saudis” in his first extensive public remarks on the topic.