Riot fear over Charles and Diana's wedding
Margaret Thatcher secretly discussed issuing firearms to the police amid fears riots could disrupt the wedding of the Prince of Wales and Lady Diana Spencer.
Files released by the National Archives in Kew, west London, under the 30-year rule, show the Metropolitan Police Commissioner was so concerned about the security situation he even raised it with the Queen.
In 1981, Mrs Thatcher's Conservative Government was rocked by the worst outbreak of civil unrest since Victorian times as rampaging youths battled the police in cities across England.
During the spring and summer, an explosive cocktail of inner city deprivation, rising unemployment, racial tensions and resentment at police tactics reached boiling point.
After riots erupted in Brixton, south London, in April, a fresh wave of disturbances broke out at the beginning of July - the month of the royal wedding - centred on Toxteth in Liverpool.
Further riots broke out in other cities, prompting fears of a breakdown of law and order.