“Based on press reporting, I’m asking for Congress to open an investigation of whether any US Intelligence was shared with Saudi Arabia that led to political persecution or killing,” he wrote.

Khashoggi was killed in a “fistfight” in the Saudi Consulate in Istanbul, the kingdom claimed early Saturday, finally admitting that the writer had been slain at its diplomatic post. Authorities said 18 Saudi suspects were in custody and intelligence officials had been fired.

The overnight announcements in Saudi state media came more than two weeks after Khashoggi, 59, entered the Saudi Consulate in Istanbul for paperwork required to marry his Turkish fiancee, and never came out. They also contradicted assertions in Turkish media leaks that Khashoggi was tortured, killed and dismembered inside the consulate, claims the kingdom had previously rejected as “baseless.”

The Associated Press contributed to this report