The son of Sharjah's ruler died aged 39 in London yesterday after unconfirmed reports of a 'drug-fuelled orgy'.

Men's fashion label owner Sheikh Khalid bin Sultan Al Qasimi was the son of Sheikh Dr Sultan bin Muhammad Al Qasimi, who rules the city in the United Arab Emirates.

Sources said a quantity of Class A drugs had been found at the penthouse flat in Knightsbridge where his body was discovered but the police have yet to confirm or deny this.

Officers were said to have found the drugs after being called in by medics, according to The Sun.

A source told the same publication: 'There had apparently been a party where some guests were taking drugs and having sex.

'It is suspected that Sheikh Khalid may have died suddenly as a result of taking drugs. As well as the police inquiry, an urgent internal probe has been ordered and staff have been ordered to keep quiet.'

The source added that Qasimi enjoyed the freedoms that London offers but that his story 'has ended tragically'.

The high-end apartment block where his body was found boasts a dozen homes that sell for up to £90 million.

The Sheikh's friend and former business partner Elliott Frieze said last night: 'He was incredibly hard working and talented. He was a wonderful person.'

No arrests have been made in the 'unexplained' tragedy, as detectives are describing it. Flags in Sharjah have been ordered to fly at half mast as three days of national mourning begin.

Tributes have flooded in on social media expressing condolences to the Emir, who lost another son aged 24 in 1999.

The ruler (pictured) is mourning the death of his second son as flags in the UAE are ordered to fly at half-mast

His death has been described as 'unexpected' by members of his team.

The prince was born in Sharjah but moved to the UK aged nine where he was educated at the prestigious Tonbridge School in Kent.

He studied French and Spanish at Imperial College London before moving on to an architectural degree and art school Central Saint Martins, where he studied fashion and launched his menswear label Qasimi Homme in 2008.

Its flagship UK store opened in Soho that year, with his clothes now stocked across the globe and paraded at fashion weeks in London, Paris and the Middle East.

The UAE's Ministry of Presidential Affairs said in a statement: 'President His Highness Sheikh Khalifa Bin Zayed Al Nahyan mourns with grief and sorrow, the death of Sheikh Khalid Bin Sultan Bin Mohammed Al Qasimi, the son of the Ruler of Sharjah, praying to Allah the Almighty to rest his soul in peace, and grant his family patience and solace.'

A tribute posted on his brand's Instagram account this afternoon reads: 'It is with great sadness that we report that Khalid Al Qasimi has unexpectedly passed away on 1st July 2019.

'Khalid was praised for his tenacious yet sensitive exploration of social-political issues, particularly those pertaining to the Middle East and its sometimes strained relationship with the West, a subject very close to his heart and his upbringing.

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

'The design world has lost a great philosopher and artist, and we ask that the privacy of the family, team and brand are respected at this difficult time.'

Sultan bin Muhammad Al Qasimi came into power in 1972. This is the second of his children to die.

His eldest son, Sheikh Mohammed Bin Sultan Al Qasimi, died of a heroin overdose aged 24 in 1999, the Independent reported at the time.

He was reportedly found on his bathroom floor at home in East Grinstead surrounded by syringes.

Source: Daily Mail