THE alleged 'torture murder' of a Saudi journalist comes after THREE royal princes vanished for criticising the regime.

Prince Sultan bin Turki disappeared in 2016 after boarding a plane to fly to Cairo - years before the alleged slaying of Jamal Khashoggi.

Reservations had been made for Sultan to stay at a five-star hotel, the Daily Mail reports.

He had vocally slammed Saudi Arabia for human rights abuses.

Sultan predicted his fate telling pals: "If you didn’t find me they have taken me to Riyadh. Try to do something."

He noticed the plane was flying off course and banged on the cockpit door, but was subdued by gun toting goons hidden among the plane crew.

He was reportedly driven away "kicking and screaming" when they landed and not seen again.

Prince Turki bin Bandar fled Saudi to Paris and began posting YouTube clips being critical of the regime.

He claimed to have received letters saying: "You son of a w****, we’ll drag you back like Prince Sultan."

Bandar vanished in July 2015.

Again he predicted his fate saying: "I know I will be kidnapped or they will assassinate me."

Two months later, Prince Saud bin Saif was thrown in a prison cell after backing calls for the removal of the Saudi King and Crown Prince, Muhammad bin Nayef.

Turkish officials suspect Jamal Khashoggi was killed during a visit to the nearby consulate on October 2.

His murderers are reported to have listened to music on their headphones while surgically dismembering his body.

Tonight, the Washington Post published his final ever column entitled “What the Arab world needs most is free expression."

Global Opinions editor Karen Attiah said: "The Post held off publishing it because we hoped Jamal would come back to us so that he and I could edit it together.

“Now I have to accept: That is not going to happen.”

In the piece, Khashoggi calls for a free press throughout the Arab world and singles out the Saudi kingdom for imprisoning writer Saleh al-Shehi.

“These actions no longer carry the consequence of a backlash from the international community,” he wrote about the crackdown on journalists.

“Instead, these actions may trigger condemnation quickly followed by silence.”

Meanwhile, a former UK student has been named as part of the hit squad which "tortured and killed" a Saudi journalist.

At least nine of 15 suspects identified by Turkish authorities worked for the Saudi security services, military or other government ministries.

Seven of the suspects are reportedly part of Crown Prince Mohammed bin Salman’s personal security detail.

At least three of the elite guards are reported to have accompanied him on his visit to London in March when he met the Queen in Buckingham Palace.

Earlier Donald Trump claimed the crown prince "denied all knowledge" of Khashoggi's mysterious disappearance.

The US President said the royal told him an investigation was underway and promised he would get answers surrounding the writer's fate.

This afternoon Trump revealed the US has requested audio and video from Turkey relating to missing journalist adding "if it exists".

The international writer had his fingers torn off one by one by his torturers before he was decapitated and his body was later dissolved in acid, according to horrific reports.

The journalist was allegedly carved up with a bone saw while alive in a horrifying seven-minute execution carried out by killers listening to music on headphones.

Khashoggi, an outspoken critic of the Saudi leadership, was last seen alive entering the consulate on October 2nd, however Saudi Arabia has denied killing him and initially said he left the building unharmed.

However, a source told the Washington Post they heard a recording from the writer's Apple Watch capturing the moment he was allegedly dragged into a study to be drugged and butchered.