Oman names a new leader after the death of Sultan Qaboos bin Said

Qaboos was 79, and ruled Oman for five decades before his death Friday. He overthrew his father in a bloodless coup in 1970, becoming the longest serving Arab leader. The Omani government declared three days of national mourning.

Haitham bin Tariq al-Said has been named as the new ruler, according to state-run Oman News Agency.

Qaboos did not have children or a direct heir at the time of his death. The Omani Constitution calls on the royal family to choose a new sultan within three days.

The US Embassy in the capital of Muscat said it's "deeply saddened" by Qaboos' death.

"We have lost one of the world's great leaders -- a visionary responsible for Oman's prosperity and progress for the last half century," the embassy's tweet read. "His steadfast leadership embodied his sincerity, his generosity, his tolerance, and his deep love for his country. His Majesty Sultan Qaboos will be missed not only by the people of Oman, but also by his friends and admirers the world over, including in the United States."

Former President George W. Bush described him as a "stable force in the Middle East and a strong US. ally."

"His Majesty had a vision for a modern, prosperous, and peaceful Oman, and he willed that vision into reality," Bush said. "Laura and I are fortunate to have visited him in Muscat last fall. We enjoyed his grand hospitality, and we saw how his able leadership improved education, healthcare, and the arts throughout the beautiful country of Oman."

Sultan was seen as a progressive leader

Qaboos was born November 18, 1940, according to the Oman News Agency. He was also a graduate of the Royal Military Academy Sandhurst in England and served in the British army.

As ruler, Qaboos sought to solidify ties with western allies. Oman has a particularly deep-rooted relationship with the United Kingdom. Queen Elizabeth II visited in 2010 to commemorate Oman's 40th National Day.

One of the more notable incidents during Qaboos' reign was his release of three American hikers who were arrested and charged for spying in Iran in July 2009. The three Americans were released in 2011.