A United Nations expert has said Saudi Arabia’s Crown Prince Mohammed bin Salman should be investigated for the murder of dissident journalist Jamal Khashoggi in October because of “credible evidence” that he and other senior officials are liable for the killing, The Guardian reported on Wednesday.

Agnes Callamard, the special rapporteur on extrajudicial, summary or arbitrary executions, has published a 100-page analysis of the journalist’s assassination by Saudi officials, which she called “an international crime”.

“It is the conclusion of the special rapporteur that Mr Khashoggi has been the victim of a deliberate, premeditated execution, an extrajudicial killing for which the state of Saudi Arabia is responsible under international human rights law,” Callamard said in her report.

The UN expert used recordings of conversations from inside the Istanbul consulate, where Khashoggi was killed, to piece together his last moments, and how he was confronted by Saudi officials, one of whom said: “We are coming to get you.”

Salman, the de-facto ruler of Saudi Arabia, was already widely suspected of having ordered the assassination. Even Western intelligence agencies reached the conclusion. “Assessments of the recordings by intelligence officers in Turkey and other countries suggest that Mr Khashoggi could have been injected with a sedative and then suffocated using a plastic bag,” said the special rapporteur.

In February, The New York Times reported that Mohammed bin Salman told a top aide in 2017 that he would use “a bullet” on the self-exiled journalist if he did not return to the kingdom and stop criticising the Saudi government.

Saudi Arabia has repeatedly denied Salman’s involvement in the murder, and in December 2018, condemned a United States Senate resolution accusing him of ordering the killing of the journalist. They have blamed the murder on a group of rogue Saudi officials.

The conversation between Salman and the aide Turki Aldakhil took place in September 2017, when the kingdom’s government was increasingly alarmed about Khashoggi’s criticisms. The same month, Khashoggi started writing opinion columns for The Washington Post, and top Saudi officials discussed ways to lure him back to the country, communications intercepted by US intelligence agencies reportedly showed.