A US federal court said in a filing on Tuesday that it was dismissing a lawsuit against the Saudi crown prince over the killing of Saudi columnist Jamal Khashoggi who lived in Virginia, after the state department’s determination that the prince has immunity as a head of state or government.

The lawsuit was filed on behalf of Hatice Cengiz, the fiancée of Khashoggi, who named Crown Prince Mohammed bin Salman as the most prominent defendant.

Khashoggi was killed by Saudi agents while visiting Saudi Arabia’s consulate in Istanbul in 2018 to get documents for his upcoming wedding. This September, Prince Mohammed’s father, King Salman, made the prince the Prime Minister of Saudi Arabia.

The move formalised his role as ruler of the kingdom, though the king remains the head of state. Some US officials said the king appeared to make the decision to ensure that the prince had immunity in the case.

King Salman made the announcement six days before an October deadline set by the court for the US government to advise whether Prince Mohammed had immunity.