Khashoggi murdered over 'report on Saudi chemical warfare secrets in Yemen'

Saudi journalist Jamal Khashoggi may have been murdered over a report he was preparing on the use of chemical weapons in Riyadh's devastating military campaign in Yemen.

A close friend of Khashoggi told British daily the Sunday Express on Monday that Khashoggi was gathering evidence for the damning report a week before he was killed by Saudi agents in Istanbul.

"I met him a week before his death. He was unhappy and he was worried," said the Middle Eastern academic, who spoke on the condition of anonymity.

"When I asked him why he was worried, he didn't really want to reply, but eventually he told me he was getting proof that Saudi Arabia had used chemical weapons. He said he hoped he would be getting documentary evidence."

"All I can tell you is that the next thing I heard, he was missing," the source added.

The 59-year-old journalist, who had criticised Saudi Arabia's powerful Crown Prince Mohammad bin Salman, vanished after entering Saudi consulate in Istanbul on 2 October to obtain paperwork.

Turkish security sources have said that Khashoggi's body, which has still not been found, was cut up into multiple pieces by a team of 15 Saudi operatives.

Khashoggi had been critical of the Saudi-led intervention in neighbouring Yemen that has left almost 10,000 people dead since 2015, and sparked what the UN has labelled the world's worst humanitarian crisis.

"The longer this cruel war lasts in Yemen, the more permanent the damage will be… the crown prince must bring an end to the violence," Khashoggi wrote in a Washington Post article in September.

Reports have emerged that the Saudi-led coalition has used US-supplied white phosphorous munitions in the war.