Luring dissidents to meetings to “disappear” them is a common ruse used by authorities in Saudi Arabia, a prince from the Middle Eastern kingdom said, before revealing that at least five royals have vanished in the last week alone for speaking out against the disappearance of journalist Jamal al-Khashoggi.

The prominent regime critic went missing on 2 October after he went to the Saudi consulate in Istanbul to register divorce papers, so he could marry his fiancée Hatice Cengiz. Turkish authorities have said they believe the 59-year-old was either kidnapped or killed within the consulate building, a claim denied by Saudi officials who said he left of his own accord.

Khaled bin Farhan al-Saud, a Saudi prince living in exile in Germany, told The Independent that Saudi authorities planned a similar kidnapping ploy against him just 10 days before Mr Khashoggi went missing.

He believes it is part of an escalating crackdown orchestrated by Crown Prince Mohamed Bin Salman, to silence his critics.

The 41-year-old prince said the authorities had promised his family a “large cheque” and millions of dollars if he agreed to fly to Egypt to meet regime officials at the Saudi consulate in Cairo.

He was told that the Saudi authorities had heard he was in financial trouble and “wanted to help”. They promised he would be safe.

He said at least five royals – grandsons of King Abdul-Aziz, the founder of modern Saudi Arabia – had last week attempted to voice their dissatisfaction with Mr Khashoggi’s disappearance and the crackdown, in a meeting with the authorities in Saudi Arabia. Those royals were promptly detained and their exact whereabouts are unknown, he alleged.

“Over 30 times the Saudi authorities have told me to meet them in the Saudi embassy but I have refused every time,” he said. “I know what can happen if I go into the embassy.”

He added: “Around 10 days before Jamal went missing they asked my family to bring me to Cairo to give me a cheque. I refused.”

He said there were “many princes in jail right now in Saudi”, adding: “Just five days ago a group tried to visit King Salman saying they were afraid for the future of the al-Saud family, they mentioned Mr Khashoggi’s case. They were all put in jail.”

Everyone was “scared”, he said.

The Independent reached out to the Saudi authorities and the Saudi embassy but received no response. Saudi Arabia has repeatedly denied accusations it has forcibly disappeared people.

But Khaled bin Farhan’s story eerily echoes the alleged fate of another royal, Sultan bin Turki bin Abdulaziz, who vanished in 2016 after criticising the regime.

Aides of Sultan bin Turki told The Independent the prince was lured to Cairo on a royal private jet to see his father but was drugged and flown to Saudi. He is believed to be alive but under house arrest. His friends no longer have contact with him.

Both stories mirror the incident with Mr Khashoggi who, according to his friends and family, was promised protection and a high-level job if he returned to his home country, which he left for the US in 2017 fearing incarceration.

US officials told The Washington Post that intelligence intercepts showed Crown Prince Mohamed bin Salman himself ordered an operation to lure Mr Khashoggi back home and then detain him.

Turkish authorities believe he may have been killed within the Saudi consulate building.

Crown Prince Mohammed Bin Salman (Getty)

Turkish media outlets published CCTV footage earlier this week, which they claimed showed Saudi intelligence officers entering Turkey via Istanbul airport as part of a 15-man team sent to capture Mr Khashoggi.

Turkish investigators are also looking into two Saudi private jets that landed on 2 October.

The Saudi authorities maintain Mr Khashoggi left the consulate building safely and deny any involvement in his vanishing.

But they are facing mounting pressure from Turkey and the United States to provide evidence, including CCTV footage, proving their claims.

Many princes [are] in jail right now in Saudi. Everyone is scared Khaled bin Farhan, dissident Saudi prince

Britain’s foreign secretary Jeremy Hunt has joined calls for more information, warning Saudi Arabia it faces “serious consequences” if Turkish suspicions that Mr Khashoggi was murdered turn out to be true.

“People who have long thought of themselves as Saudi’s friends are saying this is a very, very serious matter,” Mr Hunt told the Agence France Presse news agency. ”If these allegations are true, there will be serious consequences because our friendships and our partnerships are based on shared values.

“We are extremely worried.”

Members of the Turkish-Arab Journalist Association hold a protest near the Saudi Arabia consulate in Istanbul

The disappearance of Mr Khashoggi has, meanwhile, sparked panic among critics of the regime who believe his possible murder is an escalation of a “campaign of kidnapping”.

Ghanem al-Dosari, a London based Saudi satirist, told The Independent that since Mr Khashoggi went missing, critics in exile were terrified of travelling anywhere, fearing they could be “intercepted”. He said that some had become so paranoid they were not leaving their homes.

Mr Dosari has not set foot in a Saudi embassy for nearly a decade, even though his passport expired in 2010.

“[The authorities] have a history of trying to lure people into embassies, they asked me to go inside the embassy in 2010 and I refused,” he told The Independent. “I haven’t travelled in years for fear of entering a country where I might be picked up. I know dissidents who are now scared to leave their apartments.”

Aside from the princes who were arrested earlier this week, there are at least five members of the royal family, who were once untouchable, that are apparently missing.

[The authorities] have a history of trying to lure people into embassies, they asked me to go inside the embassy in 2010 and I refused Ghanem Dosari, Saudi satirist and regime critic

Prince Abdul Aziz bin Fahd, 45 the son of the late King Fahd, allegedly disappeared last year amid rumours he had been put under house arrest when Crown Prince Mohammed detained dozens of people in the Ritz-Carlton hotel as part of a massive anti-corruption drive. Khaled bin Farhan said that Abdul-Aziz bin Fahd’s family have no idea where he is, but they know he is unwell.

Also missing is Prince Khaled bin Talal, 56, the brother of Saudi billionaire Al-Waleed bin Talal, who was arrested in December last year. Again royal family members say they have no idea where he is.

Around the same time Sultan bin Turki vanished in 2016, Saud bin Saif al-Nasr, a relatively minor royal who publicly backed calls for King Salman’s removal, went missing as well.

Khaled Bin Farhan thinks Saud was also tricked into getting on a regime-owned private jet which, instead of flying to Rome, landed in Riyadh.