Abdullah was the sixth monarch of Saudi Arabia.
He was one of 42 sons.
The BBC reported:
Saudi King Abdullah bin Abdulaziz has died in hospital, state TV says.
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The announcement, made early on Friday, said his brother, Salman, had become king.
Before the announcement, Saudi television cut to Koranic verses, which often signifies the death of a senior royal.
King Abdullah, who was said to be aged about 90, had been in hospital for several weeks suffering from a lung infection.
Abdullah had more than 30 children from around a dozen wives.