According to the CNN broadcaster, in over 400 messages, Khashoggi discussed plans with fellow Montreal–based Saudi exile, Omar Abdulaziz, who received asylum in Canada.
"The more victims he eats, the more he wants. I will not be surprised if the oppression will reach even those who are cheering him on," Khashoggi said in a message in May. The broadcaster was given access to the texts.
According to CNN, in August, the two understood that their messages might have been intercepted by Saudi authorities.
"God help us," the journalist wrote.
On Sunday, Abdulaziz brought a lawsuit against an Israeli firm that is believed to be behind the software that was allegedly used to hack his phone, the media outlet said.
Khashoggi, a Washington Post columnist known for his criticism of Saudi policies, disappeared on October 2 after entering the Saudi consulate in Istanbul. Saudi Arabia's claim that the journalist had been killed in a fight inside the consulate came after two weeks of denials and growing pressure from Western allies to provide explanations.
On October 26, the Saudi prosecutor general acknowledged that the journalist's murder had been premeditated, although Riyadh continues to maintain that the extrajudicial killing was not at the behest of the Saudi royal family, describing it as a 'rogue' operation.