Prosecutors in Istanbul announced Wednesday that they have prepared an indictment of a close aide to Saudi Arabia’s Crown Prince Mohammed bin Salman and a former deputy head of general intelligence over the killing of Washington Post journalist Jamal Khashoggi.

The two men, former deputy head of Saudi Arabia’s general intelligence Ahmed al-Asiri and former royal court adviser Saud al-Qahtani, are accused of having “instigated premeditated murder with monstrous intent.” The indictment also includes the names of 18 suspects who allegedly actually carried out the killing. The list of alleged killers consists of a 15 person team who traveled to Turkey to carry out the operation, and three intelligence officials.

Khashoggi was last seen on October 2, 2018, entering the Saudi consulate in Istanbul. He had gone to the consulate to obtain documents for his upcoming wedding, and his fiancee was waiting outside. Khashoggi never emerged from the consulate. His remains have not been found, and the Turkish government has alleged that his body was dismembered and removed from the building.

It is widely believed that Khashoggi was killed by the Saudi government to silence his criticism of their regime. Many western governments have also alleged that the killing was ordered by Crown Prince Mohammed Bin Salman, a claim that has also been supported by the US Central Intelligence Agency.

The Saudi government has so far declined to respond to the indictment. However, Agnes Callamard, the UN investigator who directed the international probe into the crime, welcomed the indictment, saying it was needed as a “counter balance to the travesty of justice at the hands of Saudi Arabia.” In her statement to Reuters, she also urged “U.S. authorities to release their findings on responsibility for the death of the Washington Post columnist, ‘including the responsibility of Saudi Arabia Crown Prince Mohammed Bin Salman.'”