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King Abdulaziz was the founder of the Kingdom of Saudi Arabia and Nayef bin Abdulaziz was his second son. Nayef bin Abdulaziz served as the Crown Prince of Saudi Arabia from 2012 to 2015 and as the Interior Minister of Saudi Arabia from 1975 to 2015. He was the second longest serving Interior Minister in Saudi Arabia, after his father, King Abdulaziz.