The Iranian Embassy siege took place from 30 April to 5 May 1980, after a group of six armed men stormed the Iranian embassy in South Kensington, London. The gunmen, members of an Iranian Arab group campaigning for Arab national sovereignty in the southern region of Khūzestān Province, took 26 people hostage mostly embassy staff, but also several visitors as well as a police officer who had been guarding the embassy. They demanded the release of Arab prisoners from prisons in Khūzestān and their own safe passage out of the United Kingdom. Margaret Thatcher's government quickly resolved that safe passage would not be granted, and a siege ensued. Over the following days, police negotiators secured the release of five hostages in exchange for minor concessions, such as the broadcasting of the hostage-takers' demands on British television.

By the sixth day of the siege the gunmen had become increasingly frustrated at the lack of progress in meeting their demands. That evening, they killed one of the hostages and threw his body out of the embassy. As a result, the government ordered the Special Air Service (SAS), a special forces regiment of the British Army, to conduct an assault—Operation Nimrod— to rescue the remaining hostages. Shortly afterwards, SAS soldiers abseiled from the roof of the building and forced entry through the windows. During the 17-minute raid, they rescued all but one of the remaining hostages, and killed five of the six hostage-takers.

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