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The Iranian Embassy Siege of 1980 was a siege of the Iranian embassy in London after it had been taken over by Arab separatists. The siege was ended when British special forces, the Special Air Service (SAS), stormed the building in Operation Nimrod. The incident brought the SAS to the world's attention as the whole episode was played out in front of the media.
At 11:30 on 30 April 1980 a six-man team calling itself the 'Democratic Revolutionary Movement for the Liberation of Arabistan' (DRMLA), captured the embassy of the Islamic Republic of Iran in Prince's Gate, South Kensington in central London.

Initially the terrorist's demands were for the autonomy of an Arab-majority petroleum-rich region in southern Iran known as Khuzestan (the Arabistan of the group's name); later they demanded the release of ninety-one of their comrades, alleged political prisoners of the Iranian government, held in jails in Iran.

When the group first stormed the building, 26 hostages were taken (including PC Trevor Lock, the police constable on official protection duty at the main entrance, and two visiting BBC personnel - journalist Chris Cramer and sound recordist Sim Harris - who had stopped by to pick up visas), but five were released over the following few days. Police negotiators attempted to mollify the terrorists with supplies of food and cigarettes, and on the third day a statement by the group was broadcast on the BBC Radio 2 following threats to kill a hostage (which was missed by the group as they were tuning in to Radio 4 instead). The unit's Iraqi handler had promised the group that the Jordanian ambassador would intervene to provide safe passage, but when it became clear this was not going to happen, the situation in the embassy deteriorated.

On the sixth day of the siege the terrorists killed a hostage, press attaché Abbas Lavasani, and threw his body outside. This marked an escalation of the situation and prompted Prime Minister Margaret Thatcher's decision to proceed with the rescue operation. The order to deploy a unit of the Counter Revolutionary Warfare (CRW) wing of the SAS had been given in the first few hours of the siege. At the time B Squadron were currently on CRW duty. When the first hostage was shot, the Metropolitan Police Commissioner, David McNee passed a note signed by Margaret Thatcher to the Ministry of Defence, stating this was now a "military operation".

News teams were camped outside the embassy. A unit from the British news organisation ITN, using recently-introduced ENG camera equipment, managed to establish a viewpoint at the rear of the embassy. It was images from this vantage point that showed the SAS raid on the building live on television after their correspondent had been 'tipped off'. However the SAS insisted on a short time-delay between the live events and their broadcast in case the terrorists were watching the broadcasts. (less info)