Turkey’s Communications Director Fahrettin Altun on Friday called on Saudi Arabia to send the murderers of Saudi journalist Jamal Khashoggi to public court with international observers on the second anniversary of his death in Istanbul.

"We all know Jamal’s killers. Let’s make them pay: Send the Saudi henchmen to Turkey. Cooperate with the criminal investigation in Turkey – the only investigation that was ever intended to shed light on what happened," Altun wrote on Twitter.

He reiterated that two years ago, Khashoggi walked into an ambush at Saudi Arabia’s consulate in Istanbul.

"Unbeknownst to him, someone in Riyadh had dispatched a death squad, including a forensic expert and a body double – with a bone saw," he added.

"Jamal’s killers have since been exfiltrated. Harbored. Brought to a show trial. Allowed to walk free," the communications director said, stressing that Turkish prosecutors, police officers and communication experts continue to work day and night to bring Khashoggi’s killers to justice.

"We serve the cause of justice and truth," Altun said.

Khashoggi, a columnist for The Washington Post, was killed and dismembered by a group of Saudi operatives shortly after he entered the country's consulate in Istanbul on Oct. 2, 2018. The whereabouts of his body are not yet known.

Turkey’s diplomatic efforts have helped to keep Khashoggi’s murder on the international community’s agenda and to further investigate the crime.

Following the incident Turkey summoned Saudi Arabia’s Ambassador to Ankara Waleed A. M. Elkhereiji on Oct. 4, 2018, to ask about the journalist’s whereabouts.

As Elkhereiji was again summoned to the ministry a few days later, President Recep Tayyip Erdoğan stated on the same day that he personally is following the issue.

Erdoğan at that time had several high-level meetings including with the Saudi king, U.S. President Donald Trump and U.N. Secretary-General Antonio Guterres to discuss the murder and steps to be taken.

Erdoğan wrote an opinion piece that was published in The Washington Post in November 2018 detailing Turkey's stance on the killing of the journalist.

"Where is Khashoggi's body? Who is the 'local collaborator' to whom Saudi officials claimed to have handed over Khashoggi's remains? Who gave the order to kill this kind soul? Unfortunately, the Saudi authorities have refused to answer those questions," the president said in the piece.

Foreign Minister Mevlüt Çavuşoğlu was another figure engaged in busy diplomacy for the investigation into the murder. Meeting with several counterparts, Çavuşoğlu also came together with Agnes Callamard, U.N. special rapporteur on extrajudicial and arbitrary executions in Ankara in January 2019.

Callamard said that Turkey’s active, comprehensive, impartial and transparent investigation was seriously sabotaged by Saudi Arabia.

In a 101-page report published by the United Nations High Commissioner for Human Rights (UNHCR) in the summer of 2019, Saudi Arabia was held responsible for "deliberately" killing Khashoggi, noting that there is documented evidence for the investigation of senior officials, including Saudi Crown Prince Mohammed bin Salman (MBS).

In September, the Saudi chief prosecutor announced the final verdicts for eight defendants tried in the Khashoggi case. Five of the defendants were sentenced to 20 years, one to 10 years and the two remaining to seven years each in prison.

Justice was denied by the failure to disclose the identities of the defendants or who got which sentence, strengthening allegations that the trial was merely a cover-up.

Khashoggi's murder caused an international crisis that turned many eyes toward Saudi Arabia, especially to MBS. Turkey has shouldered most of the responsibility of bringing justice to the perpetrators, given that the international community and the kingdom have failed to conduct a proper, objective trial on the case.

Turkish prosecutors in September prepared a second indictment against six Saudi officials in connection with the 2018 murder.

The indictment filed by the Istanbul chief public prosecutor's office demanded aggravated life imprisonment for two suspects for the crime of gruesome premeditated murder.

It was also reported that the charges against the other four carried sentences of up to five years in jail.

The reports did not specify whether the six suspects were among those already being tried in absentia in an Istanbul court for Khashoggi's killing.

The first public trial in Khashoggi's murder against 20 Saudi nationals opened in Istanbul in July.

However, Saudi Arabia refused to extradite the suspects, including Ahmed al-Asiri, ex-deputy chief of Saudi intelligence and Saud al-Qahtani, a former adviser to MBS.

Meanwhile, Hatice Cengiz, the fiancee of Khashoggi, called on world leaders Thursday not to participate in this year's G-20 summit in Riyadh.

In an article in The Washington Post on the eve of the second anniversary of Khashoggi's murder, Cengiz recalled that Saudi Arabia will be hosting the 15th annual summit of leaders of the Group of 20 economies in November.

"The most logical thing for world leaders to do today – the best punishment for the Saudi crown prince right now, even if it comes too late – is not to attend this virtual summit," said Cengiz in her piece titled "We have been deprived of Jamal Khashoggi's voice. But his silence says it all."

"This would be a way to avoid giving any additional legitimacy to the current Saudi administration that bears the responsibility for this murder and is still managing to escape its consequences," she added.

The summit will be held virtually on Nov. 21-22 and chaired by King Salman.