A mysterious sign was flown over Los Angeles on Thursday with a message directed at Prince Harry, who was in the city to attend the ESPY Awards with Meghan Markle.

On the day the royal accepted the Pat Tillman Award for Service at the red-carpet event, a plane towing a banner was photographed flying overhead, bearing the message: "PRINCE HARRY: INVESTIGATE MUMIS DEATH."

The pilot responsible for flying the sign and its commissioners have not been identified. Newsweek approached representatives of Prince Harry via email for comment.

Prince Harry wears a black suit at the ESPY Awards in Los Angeles, July 11, 2024. And (inset) a mysterious sign flown over L.A. at the time of the ESPY Awards directed at Harry. The... Prince Harry wears a black suit at the ESPY Awards in Los Angeles, July 11, 2024. And (inset) a mysterious sign flown over L.A. at the time of the ESPY Awards directed at Harry. The meaning behind the sign and who commissioned it are unknown. Kevin Mazur/Getty Images for W+P/Tommaso Boddi/FilmMagic

The intention behind the sign and the "death" it is referring to is unknown. However, it could appear to be a reference to the death of Harry's mother, Princess Diana, whom he referred to as "mummy" throughout his 2023 memoir, Spare.

Diana's death from injuries sustained in a 1997 Paris car crash when she was just 36 years old has become the basis for a number of conspiracy theories over the years. They range from unfounded claims that she was murdered by the British state to suggestions she was pregnant at the time of the accident.

In 2006, an 800-page report was compiled assessing the evidence surrounding the princess' death and addressing 20 of the core conspiracy theories that were proposed by Mohamed al-Fayed. He was the father of Dodi Fayed, Diana's boyfriend at the time of her death and who died alongside her in the Paris crash.

Named "Operation Paget," the report was compiled using extensive interviews with the people closest to Diana before her death, including Prince William and the friends she spoke to in her final days. It also looked at forensic evidence gathered from the crash wreck and site, as well as CCTV footage.

The report informed the lengthy formal inquest into the princess' death in 2007. It reached a verdict in April 2008 and attributed her dying to several key factors, principally the reckless driving of Diana's chauffeur at the time of the accident and also of the paparazzi members who followed in pursuit. The inquest also raised that partial cause could be attributed to the fact that none of the car's inhabitants was wearing seat belts at the time of the crash.

The inquest was intended to close a door on a painful chapter of British history and to let the memory of the princess rest in peace. However, for some, it did not reach a satisfying conclusion.

Notably, among those who distrusted the inquest's verdict was Prince Harry.

Prince Harry plays on a slide with Princess Diana at Highgrove House in Gloucestershire, England, July 18, 1986. The prince discussed the 2007 inquest into his mother's death in his memoir "Spare." Prince Harry plays on a slide with Princess Diana at Highgrove House in Gloucestershire, England, July 18, 1986. The prince discussed the 2007 inquest into his mother's death in his memoir "Spare." Tim Graham Photo Library via Getty Images

In his memoir, Spare, he described the written report as "a joke," telling readers that it was an insult and that Prince William agreed with him. The paparazzi's role in his mother's death, he felt, was never appropriately acknowledged with no one facing justice. Harry added that some questions went without answers.

In an interview with 60 Minutes' Anderson Cooper at the time of the book's publication, Harry said that he and William had considered asking for a new inquest.

"William and I had already been told, 'The event was like a bicycle chain. If you remove one of those chains, the result would not have happened.' And the paparazzi chasing was part of that. But yet, everybody got away with it," Harry added.

"William and I considered reopening the inquest. Because there were so many gaps and so many holes in it, which just didn't add up and didn't make sense."

When asked if he would actually go through with it, Harry responded: "I don't even know if it's an option now. But no, I think... would I like to do that now? It's a hell of a question."

Harry has not discussed the prospect of reopening the inquest since his memoir's publication, but his comments serve as an ever-present reminder that questions surrounding the death of Diana persist. The princess remains a cultural icon, with the events leading up to and immediately after her death only recently being dramatized for the screen by Netflix for its royal drama, The Crown.

James Crawford-Smith is Newsweek's royal reporter, based in London. You can find him on X (formerly Twitter) at @jrcrawfordsmith and read his stories on Newsweek's The Royals Facebook page.

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