Saudi Arabia sent a two-man “clean-up team” to erase evidence of journalist Jamal Khashoggi's killing a week after he disappeared at the Saudi consulate in Istanbul, a Turkish official said on Monday, calling it a sign top Saudi officials knew of the crime.

Confirming a report in Turkey’s pro-government Sabah newspaper, the official said the chemist and toxicologist were tasked with erasing evidence before Turkish investigators were given access to the Saudi consulate and consul’s residence.

Sabah identified the two men as Ahmed Abdulaziz al-Jonabi and Khaled Yahya al-Zahrani, saying they arrived in Turkey as part of an 11-person team sent to carry out the inspections with Turkish officials. Khashoggi, a Washington Post columnist critical of the Saudi government and its de facto ruler Crown Prince Mohammed bin Salman, disappeared at the consulate on October 2.

Saudi officials initially insisted Khashoggi had left the consulate, then said he died in an unplanned “rogue operation”. The kingdom’s public prosecutor Saud al-Mojeb later said he was killed in a premeditated attack.

Turkish and Saudi officials have carried out joint inspections of the consulate and consul's residence in Istanbul, but President Erdogan says some Saudi officials are still trying to cover up the crime. Ankara has also demanded Riyadh cooperate in finding Khashoggi’s body, which Istanbul’s chief prosecutor said had been dismembered.

A senior Turkish official confirmed the names of the men identified on Monday by Sabah. “We believe that the two individuals came to Turkey for the sole purpose of covering up evidence of Jamal Khashoggi’s murder before the Turkish police were allowed to search the premises.”