"The objective of the murder was clear, to halt Khashoggi's advocacy in the US for democratic reform in the Arab world," the BBC quoted the lawsuit as saying.
It added that Khashoggi, also a prominent critic of the Saudi government, was murdered "pursuant to a directive of defendant Mohammed bin Salman".
After filing the lawsuit, the lawyers for Cengiz and the rights body said in a video conference that its focus was to have a US court hold the Crown Prince "liable for the killing and to obtain documents that reveal the truth".
In a statement, Cengiz said: "Jamal believed anything was possible in America and I place my trust in the American civil justice system to obtain a measure of justice and accountability."
Khashoggi, a prominent journalist known to have covered the Soviet invasion of Afghanistan and the rise of the late Al Qaeda leader Osama bin Laden, was killed by a team of Saudi agents during a visit to the Kingdom's consulate in Istanbul on October 2, 2018, to obtain papers he needed in order to marry Cengiz.
In its probe, the Saudi public prosecution concluded that the murder was not premeditated, the BBC reported.
It said the killing was ordered by the head of a "negotiations team" sent to Istanbul to bring Khashoggi back to the Kingdom "by means of persuasion" or, if that failed, "by force".
The slain journalist's remains remain missing till date.
Last December, the Riyadh Criminal Court sentenced five people to death for "committing and directly participating in the murder of the victim", while three others were handed prison sentences totalling 24 years for "covering up this crime and violating the law".
But, the state media reported last month that the five death sentences were commuted to 20-year jail terms.
The Crown Prince has denied involvement in the murder.
(Only the headline and picture of this report may have been reworked by the Business Standard staff; the rest of the content is auto-generated from a syndicated feed.)
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