Police searches in raids across West London and Buckinghamshire had led to the arrest of four suspected Islamic terrorists, aged 18 to 27, who were planning to stab Queen Elizabeth to death at the Royal British Legion Festival of Remembrance on Saturday.

The British Sun reports that the police continues to question the four extremists arrested on suspicion that they were committing, preparing or instigating acts of terrorism under Britain's Terrorism Act 2000. Authorities have also confiscated computers and documents from the suspects' homes and these evidences are being examined.

Like Us on Facebook

Besides the arrest of the four, whom police believe have direct ties with Syria and are jihadists, the police also searched several homes and cars in Greenford, Hounslow, Brentford and Walthamstow as part of its ongoing probe into terrorism related to Islamist extremist groups.

The British monarch, 88, has been informed of the plan to kill her, and in spite of the danger to her life, she and Prime Minister David Cameron would still attend the Sunday Remembrance at the cenotaph in central London. The event commemorates the end of World War I in 1918, where the Queen would lay a wreath in Whitehall and also visit Edinburgh, Cardiff and Belfast.

It's also the centennial of the start of World War I, marks the 70^th year since the D-Day landing and the end of UK's conflict in Afghanistan.

Cameron said the three anniversaries make this year's celebration especially poignant. He said, quoted by BBC, "We owe each and every member of our armed forces and the families, who support them a tremendous debt - one that can never be repaid - and I pay huge tribute to their bravery and resolve."

Other members of the British royal family such as the Prince Phillip, Prince Charles and Camilla and Prince William and the pregnant Kate Middleton would also attend the events. In Glasgow at the cenotaph in George Square, the finale is a two-minute silence while poppy petals descend from the roof, representing British soldiers who died while fighting during World War I.

British Home Secretary Theresa May raised in August, the national terror threat to "severe" from "substantial," which is the second-highest threat of five threat levels. The change is due to possible retaliation by Islamic State extremists and al-Qaeda followers for UK participation in the U.S.-led air strikes in Syria and Iraq.

This is not the first attempt to assassinate the Queen, which all failed.

Marcus Serjeant, 17, fired six shots at the monarch in 1981 while she was riding her horse for the Trooping the Colour rite. Police later discovered Serjeant, jailed for five years, fired only blank shots. After one year, 31-year-old Michael Fagan was able to enter the Queen's bedroom in Buckingham Palace. He was confined for six months in a psychiatric hospital but was not charged with trespassing.

The oldest plot was in 1970, the Lithgow Plot, while the Queen and Prince Phillip were in Australia on a royal tour. The train they were riding his a big log deliberately placed on the rails to cause an accident, but the train was moving slowly as just ran over the log.

TagsQueen Elizabeth II, festival of remembrance, Remembrance Day