The DRFLA claims to have taken part in the 1979 Iranian Revolution, assisting Ayatollah Ruhollah Khomeini's uprising which overthrew the Shah, Mohammad Reza Pahlavi, and subsequently established an Islamic republic, effectively ending the millennia-old inherited Persian monarchies. However, shortly after the revolution, the DRFLA began an insurgency in Khuzestan. In 1980, DRFLA militants besieged the Iranian embassy in London and took 26 hostages, threatening to execute them unless the United Kingdom secured the release of 91 Arabs incarcerated in various Iranian prisons. They also demanded that all the Arab states' diplomatic ambassadors in London mediate on their behalf with the British government. The British Prime Minister Margaret Thatcher responded by authorizing Operation Nimrod to free the hostages. After negotiations with the Arab militants became bogged down, the Special Air Service stormed the building and killed the DRFLA leader, Oan Ali Mohammed, along with all but one of the other militants while suffering no fatalities themselves. After this incident, the DRFLA did not take part in any major militant attacks and remained largely inactive until the Iraqi invasion of Iran, where they sided with Iraq as open belligerents in the ensuing Iran–Iraq War. The group has been defunct since 1980, with its spiritual successor being the currently-active Arab Struggle Movement for the Liberation of Ahvaz (ASMLA).