Story highlights

NEW: Salman bin Abdulaziz is a half-brother of King Abdullah

He becomes next in line to the throne of the oil-rich kingdom

Salman retains his post as defense minister and becomes deputy prime minister

His predecessor, Prince Nayef, was buried Sunday

(CNN) —  

Funeral services were held Sunday for Saudi Crown Prince Nayef bin Abdulaziz, a hard-line conservative credited with pushing back al Qaeda.

His appointment comes a day after burial services for Crown Prince Nayef bin Abdulaziz, whose death was announced Saturday.

Salman, 76, who was already defense minister, retains that post and becomes deputy prime minister as well, the Saudi Press Agency reported Monday, citing a royal order. He is a brother of the late King Fahd and Crown Prince Nayef, and a half-brother of King Abdullah.

He became defense minister in November.

Salman’s official biography on the website of the kingdom’s Interior Ministry says he had memorized the Quran by the age of 10.

Nayef, a hard-line conservative credited with pushing back al Qaeda, was interior minister as well as crown prince. Prince Ahmed bin Abdulaziz is replacing him as interior minister, the Saudi Press Agency said.

Nayef, named crown prince in October by his brother the king, was heir to the Saudi throne. Saudi state TV, which reported his death Saturday, broadcast Quran readings as an expression of mourning for the prince, who died in Geneva, Switzerland. He was in his late 70s.

Saudi state TV, which reported his death Saturday, broadcast Quran readings as an expression of mourning for the prince, who died in Geneva, Switzerland. He was in his late 70s.

“It is a shock. We all knew his health was frail, but his death is a shock,” Saudi Foreign Ministry spokesman Osama Nogali said. “We still don’t know the reason behind his death.”

Saudi King Abdullah was in attendance at the funeral, along with Gen. Hussein Tantawi, head of Egypt’s Supreme Council of the Armed Forces.

U.S. President Barack Obama released a statement Saturday offering his condolences.

“Under his leadership, the United States and Saudi Arabia developed a strong and effective partnership in the fight against terrorism, one that has saved countless American and Saudi lives,” Obama said.

He praised Nayef for supporting a broad partnership between Saudi Arabia and the United States.

U.S. Vice President Joe Biden similarly offered his condolences, and hailed the former leader as an important ally in the fight against terror.

Nayef served as Saudi interior minister since 1975, overseeing the kingdom’s counterterrorism efforts.

A classified U.S. Embassy cable leaked by the website WikiLeaks described Nayef as a hard-line conservative who was lukewarm to King Abdullah’s reform initiatives.

Nayef led the crackdown against hard-line Islamists who took control of Mecca in 1979 and also oversaw the smashing of Saudi-based al Qaeda cells in the mid-2000s.

In recent years, his son, Prince Mohammed bin Nayef, has led the kingdom’s fight against al Qaeda as the elder Nayef seemed to have taken more of backseat.

CNN’s Nima Elbagir, Rima Maktabi, Hamdi Alkhshali, Mohammed Jamjoom, Caroline Faraj and Kevin Flower contributed to this report.