Less than a month before Prince Harry and Prince William are set to reunite to honour their late mother Princess Diana on what would’ve been her 60th birthday on July 1, the pair have received devastating news.

Ten members of the HALO Trust, an organization that the late icon worked closely with, were killed Wednesday and another 16 were injured by an armed group at a mine clearance camp in Afghanistan. Since Diana’s death, Prince Harry has followed in his mother’s footsteps, supporting the organization.

The HALO Trust (Hazardous Area Life-support Organization) helps removes debris left behind by war, in particular landmines.

RELATED: Meghan Markle And Prince Harry Welcome Daughter Named After Queen Elizabeth And Princess Diana, Queen ‘Delighted’

The humanitarian organization confirmed the sad news on Twitter:

Diana famously walked through one of HALO’s minefields in Angola in 1997. The visit prompted the Ottawa Mine Ban Treaty to be signed, calling for all countries to rid the world of landmines.

In 2019, 22 years later, Harry returned to the same minefield to bring even more awareness to the cause.

RELATED: Prince Harry’s ‘HRH’ Removed From Princess Diana Exhibit After Clerical Error

Princess Diana. Photo: CPImages
Princess Diana. Photo: CPImages
Prince Harry. Photo: Getty Images
Prince Harry. Photo: Getty Images

Following the devastating news, Prince Harry shared a statement expressing his condolences.

“These workers put their lives on the line every day to make the world a safer place. This brutal act reminds us that we must stand in solidarity with humanitarian aid workers and the communities they serve,” he wrote in part. “I would urge all of HALO’s supporters across the world to rally to their cause and help in any way they can.”

Read Harry’s full statement here.

The Duke of Cambridge and the Duke of Sussex will reunite in London on July 1 to honour their mother on what would have been her milestone birthday. The brothers will both attend the unveiling of a statue of Diana at Kensington Palace, which is being installed in the Sunken Garden.