In the wake of the 1972 Munich Olympics massacre, military commanders gave soldiers carte blanche to shoot hostages should nuclear weapons be the target of terrorists. The murder of Israeli athletes at the Games sent a wave of panic through Western governments at the bloody arrival of a new breed of terrorism. In Britain, the atrocity struck such fear into the hearts of military chiefs that they believed their nuclear weapons could be the next target.

A top-secret document obtained by The Independent under the Freedom of Information Act details how the Ministry of Defence made preparations for an attempt by terrorist groups including the IRA and Black September, the Palestinian extremists behind the Munich killings, to ambush military convoys carrying nuclear bombs and set off a "dirty-bomb" explosion.

The file shows that after the attack at the Olympics, which ended in the murder of 11 Israelis by their Palestinian captors after a bungled rescue attempt by German police, the MoD drew up new guidelines based on the knowledge that a well-trained terrorist group would be capable of arming a stolen nuclear weapon "within a small number of hours", and cleared a "recapture force", led by the SAS, to open fire on hijackers and any hostages to regain or destroy the bomb.