Sharjah is mourning the loss of its ruler's son, Sheikh Khalid Bin Sultan Bin Mohammad Al Qasimi, who was found dead at his home in London on Monday.

The 39-year-old son of Sheikh Sultan Bin Mohammad Al Qasimi, Supreme Council Member and Ruler of Sharjah, had founded and worked as the creative director of his eponymous fashion label QASIMI.

According to the BBCLondon police said his death is being treated as "unexplained."

According to the police statement, London's Metropolitan Police had reportedly been notified of  "a sudden death at a residential property in Knightsbridge." A post-mortem examination performed on Tuesday proved inconclusive and authorities are now carrying out additional tests.

The UAE has announced a three-day mourning period, during which the nation's flags will be flown at half-mast. 

The Emirati royal was laid to rest in Jubail graveyard on Wednesday morning, whereby rulers of Emirates, sheikhs, top officials, and well-wishers joined the funeral prayer at King Faisal Mosque.

QASIMI announced the passing of its founder in a statement shared on its online platforms. The brand highlighted Sheikh Khalid's fruitful career, noting he had showcased his work on men's fashion at the London Fashion Week and Paris Fashion Week.

According to the label, Sheikh Khalid was born in the UAE and raised in the UK, where he studied both architecture and fashion design at Central Saint Martins, a public tertiary art school in London.

"The design world has lost a great philosopher and artist," the statement read.

His collections often included cultural and political references, particularly those pertaining to the Middle East and its "sometimes strained relationship with the West."

"His goal was to a 'create a world of beautifully crafted products infused with cultural, social and political undertones to inform and inspire'," according to his brand.

Several local and international figures have paid their respects to Sheikh Khalid's family.

Dubai Ruler and Vice President and Prime Minister of the UAE, Sheikh Mohammed bin Rashid Al Maktoum, posted a tweet expressing his "sincere condolences" to Sheikh Sultan, the people of Sharjah, and the entire UAE population"I ask God to give my brother Sheikh Sultan patience during this difficult time," he wrote.

Patrick Moody, the British ambassador to the UAE, also tweeted his "deepest condolences" to Sheikh Sultan and his family.