Saudi Crown Prince Nayef, the anti-reform Wahhabi interior minister, died Saturday in a foreign hospital. The Associated Press reports:

Crown Prince Nayef, the hardline interior minister who spearheaded Saudi Arabia’s fierce crackdown crushing al-Qaida’s branch in the country after the 9/11 attacks in the United States and then rose to become next in line to the throne, has died. He was in his late 70s.

A statement by the royal family said Nayef died Saturday in a hospital abroad. It did not specify where. Nayef had been out of the country since late May, when he went on a trip that was described as a “personal vacation” that would include medical tests.

Questions and concerns about the succession process dominated the Twitter buzz as Nayef’s name trended worldwide this morning.

76-year-old defense minister Prince Salman has been mentioned as a likely successor.