Egyptian President Hosni Mubarak's grandson died abruptly, the president's office said Tuesday, declining to give a cause of the 12-year-old boy's sudden death. Mohammed Mubarak passed away Monday after a "health crisis lasting two days," the presidency said in a brief statement. State media reported he had been flown to Paris for emergency treatment, where he was joined by his grandmother, Egyptian first lady Suzanne Mubarak. His body was flown back Tuesday to Egypt for an immediate burial, according to Islamic tradition. Mohammed was the child of Mubarak's son Alaa, 47, a prominent businessman who is not involved in politics. Alaa has another son, Omar, who is 6 years old. The 81-year-old president is believed to be grooming his other son, Gamal, to succeed him. Egyptian TV and radio broadcast religious songs and programs throughout the day. The northern Cairo suburb of Heliopolis, home to the president, was under heavy security during the child's funeral, which was attended by top state officials and prominent businessmen. A TV broadcast showed a visibly distraught Alaa Mubarak, praying next to his brother Gamal at the funeral. The Mubarak brothers then carried the casket, draped in an Egyptian flag, at the head of a procession. Speculation has been rife in the Egyptian media over the cause of death, including suggestions that the boy died from a brain aneurysm, childhood leukemia or food poisoning. Egyptians first caught a glimpse of Mohammed when he appeared in photographs with his grandfather on the pages of the leading state-owned daily Al-Ahram a decade ago. It was rare glimpse of the stern president's human side as he and his wife played with the child. Mubarak is scheduled to visit the United States on May 26 to meet with President Barack Obama for the first time since he assumed office.