Britain's Queen Elizabeth II
Britain's Queen Elizabeth IIAFP file

British intelligence sources have identified a plot by local jihadists commandeered by Islamic State (ISIS) leaders in Syria to assassinate Queen Elizabeth next Saturday, reports the UK Daily Mail.

The planned attack is to target the 70th VJ Day (Victory in Japan) marking the end of World War II, and in particular it aims to kill the Queen of England - the warning has triggered British security to beef up its presence dramatically.

The incident brings to mind events last September, when "credible" threats were received of an ISIS plot to assassinate Pope Francis. Security was boosted, and fortunately the alert passed without further incident.

But now police and MI5 in Britain are racing to find the jihadists behind the plot, with no arrests made yet. The queen has stated that she will attend the VJ Day celebrations regardless, undeterred by the threat.

The attack plan orchestrated from Syria is reportedly to involve detonating a pressure cooker bomb during the VJ Day events in Central London.

Pressure cooker bombs were most notably used in the 2013 Boston Marathon bombing, in which two pressure cookers were detonated at the finish line, murdering three and wounding over 260 others. The UK hasn't seen a large scale attack since the July 7 London bombings in 2005, in which four suicide bombers murdered 52 people and wounded over 700 in an attack on the Tube subway.

Aside from Queen Elizabeth, Prince Charles is another possible target.

Several other members of the Royal Family, as well as Prime Minister David Cameron, various public figures, over 1,000 World War II veterans and their families, and thousands of members of the public will take part in the event on the streets around Whitehall and Westminster Abbey, with fears high that an explosion would cause a massive loss of life.

The day's events will start with Queen Elizabeth taking part in a service at St Martin-in-the-Fields in Trafalgar Square. The dignitaries will then proceed to Horse Guards Parade for various other ceremonies before the day's centerpiece, a parade of veterans and current troops down Whitehall to Westminster Abbey. The entire affair will be broadcast on live TV by BBC.