More than 100 of the 298 passengers on board Malaysia Airlines flight MH17 were on route to a major AIDS conference in Melbourne, several Australian media sources reported Friday morning.
Delegates to the 20th International AIDS Conference in Melbourne due to start on Sunday were told on Friday morning that about 100 medical researchers, health workers and activists were on board the plane that crashed over eastern Ukraine after being hit by a surface-to-air missile, reports in The Australian, the Star Observer and the Age said.
Both the Ukrainian government and pro-Russian rebels fighting in the region denied responsibility for the crash.
There were no survivors on board MH17, a Boeing 777 jet, which was en route from Amsterdam to Kuala Lumpur.
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Among the lives lost was leading AIDS researcher and former International Aids Society President Professor Joep Lange.
Lange had worked in HIV research and treatment since 1983. He was instrumental in pivotal antiretroviral therapy trials and on the prevention of mother-to-child HIV transmission.
President of the International AIDS Society and co-chair of the International AIDS Conference 2014, Professor Françoise Barré-Sinoussi, expressed her condolences at a prearranged event at the National Press Club in Canberra.
"Right now our thoughts are with their family. It will be a great loss for the HIV/AIDS community," she said.
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Also on board was a Geneva-based spokesman for the World Health Organization, Glenn Raymond Thomas, and Pim de Kuijer, a prominent AIDS activist from the Netherlands.
The International AIDS Society released a statement expressing its sadness over the news that a number of delegates were on board MH17, but no exact number has been confirmed by the conference organizers or Malaysia Airlines.
Twitter users took to the site to express their condolences
"How do we measure how much a person has done for humanity?" dozens of AIDS workers on crashed Malaysian jet: reports
Australia's National AIDS Trust paid tribute to the Professor on Twitter:
Reports Joep Lange died in Malaysian plane crash today, with other scientists on way to @AIDS_conference. Desperately sad news.
What a HUGE loss to the world. Just learned that dear friend, amazing father to 5 girls and veteran AIDS researcher Joep Lange was on #MH17
Saddened to learn that my friend and @WHO staff who was traveling to @AIDS_conference to Melbourne was on flight #MH17. RIP #Glenn Thomas
Former U.S. President Bill Clinton, Virgin Founder Richard Branson and Irish musician and political activist Bob Geldof are among those due to speak at the conference taking place between the 20 and 25 July.