Queen Elizabeth II leaves the Sunday service at Wolferton Church in Norwich, England, on Jan. 19, 2014. Getty Images

Islamic State group extremists allegedly planning to attack Queen Elizabeth II over the weekend have been coordinating for months and have people already stationed in the Britain, Sky News reported exclusively Tuesday. While conducting an undercover investigation into the online recruiting techniques of the Islamic State group -- also known as ISIS or ISIL -- Sky News journalists found that senior members of the organization were encouraging Britons to launch lone-wolf attacks within Britain as opposed to traveling to their headquarters in Syria. They also specifically mentioned the plot to assassinate the queen.

The reporters created two fictional personas, one male and one female, that they used to communicate with ISIS recruiters on social media. One ISIS member, who identified herself as English punk rocker Sally Jones, told the journalists that ISIS "already has a number of potential bombers in the U.K. -- some of whom have been trained in Syria and are ready to attack," Sky News reported.

ISIS reportedly sent the journalists guidebooks on how to raise money and create weapons. When one of the reporters balked at creating a bomb, Jones "revealed she had another potential bomber in Scotland and two others who so far had failed to attack." Then she relayed the plan to kill the queen, which Sky News reported to the police.

News of the assassination plot broke when the Mail ran an anonymously sourced story on Sunday about ISIS' intent to bomb the queen at her public appearances on VJ Day, an observance that marks the date Japan surrendered in World War II. Saturday will be VJ Day's 70th anniversary, and several members of the royal family were due to attend commemorative events.

But the Metropolitan Police told reporters that people should stay calm, International Business Times previously reported. "While the U.K. threat level from international terrorism remains severe, we would like to reassure the public that we constantly review security plans for public events, taking into account specific intelligence and the wider threat," they said in a statement. "The public are encouraged to continue with their plans to attend or take part in events as normal.”