A former Dubai policeman, who documented his battle with cancer on social media, died on Tuesday.
Khalifa Al Muhairi, 30, had been suffering from stage four lung cancer, after having the illness diagnosed in 2013.
He had been undergoing debilitating three-week courses of chemotherapy when he died.
He last posted to his Instagram account on June 20, from The City Hospital in Dubai, where he was having his 31st round of chemotherapy. He accompanied his post, which showed him wearing an oxygen mask, with a prayer for good health.
Tributes to Al Muhairi flooded in on social media under the trending hashtag #khalifa_dafoos.
Sheikh Mohamed bin Zayed, Crown Prince of Abu Dhabi and Deputy Supreme Commander of the Armed Forces, offered his condolences to Al Muhairi's family, describing him as an "inspiring source of optimism, hope, patience and positivity."
Sheikh Hamdan bin Mohammed, Crown Prince of Dubai, who had helped pay for some of Al Muhairi's treatment last year was among those to pay his condolences.
He posted a prayer, along with an image of himself with Al Muhairi, saying "A young hero is gone but has left hope and optimism behind him."
Sheikh Maktoum bin Mohammed, Deputy Ruler of Dubai, posted his condolences on Twitter, saying "Khalifa was an inspiring example to all Emiratis in his patience and the strength of his resolve in the face of challenges, no matter how great.
"God bless you, our hero."
Al Muhairi made headlines last year for posting an emotional video message on Instagram, appealing for financial help after doctors told him the bill for his cancer care would likely hit Dh3 million.
His plea was answered by Sheikh Hamdan, who stepped in to offer to pay for his treatment.
At the time, Al Muhairi was in the US receiving extensive treatment for cancer, and was recovering after an unsuccessful lung surgery. Medics have told him he should not expect to live more than a few years.
He became a source of inspiration after taking part in the Special Olympics Torch Relay during the World Games in Abu Dhabi in March this year, despite losing his left leg when the cancer spread.
"I was in the intensive care unit in the hospital for 35 days during my recent treatment, so I did not know if I would be able to make the torch relay when I was invited to take part," Al Muhairi told The National at the time.
“Thank God, I was well enough to be released. I’m still having chemotherapy and treatment, but I want to pay my part in spreading the message you can do anything if you put your mind to it.”
He had hoped to compete in Paralympic events in future.
“I want to be a team leader and guide other athletes.”
