In response to the Shah's defiance, the Red Army on 16 September moved to occupy Tehran. Fearing execution by the Communists, many people (especially the wealthy) fled the city. Reza Shah, in a letter handwritten by Foroughi, announced his abdication, as the Soviets entered the city on 17 September. The British wanted to restore the Qajar Dynasty to power, but the heir to Ahmad Shah Qajar since that last Qajar Shah’s death in 1930, Hamid Hassan Mirza, was a British citizen who spoke no Persian. Instead (with the help of Foroughi), Crown Prince Mohammad Reza Pahlavi took the oath to become the Shah of Iran.