Scientists were on route to the 20th international Aids conference, due to start on Sunday

This article is more than 6 years old

This article is more than 6 years old

Delegates to a key Aids conference in Australia are believed to have been on board the Malaysia Airlines plane that has crashed in Ukraine.

Scientists, researchers and other professionals were on their way to Aids 2014, the 20th international Aids conference in Melbourne. The event, to be held between 20 and 25 July, will feature former US president Bill Clinton and activist Bob Geldof.

The World Health Organisation confirmed that its employee Glenn Thomas was among the dead. British-born Thomas, who was based in Geneva and handled media relations for WHO, was heading to Melbourne for the conference. His next of kin had been informed.

A WHO spokesman said: "We are waiting for confirmation on whether there were any others from the World Health Organisation on the flight as we were sending a huge delegation to the conference. As yet, Glenn is the only one we're aware of."

The International Aids Society, which convenes the conference, expressed its “sincere sadness” at reports that delegates were on board. It said: “At this incredibly sad and sensitive time the IAS stands with our international family and sends condolences to the loved ones of those who have been lost to this tragedy.

“The IAS is hearing unconfirmed reports that some of our friends and colleagues were on board the flight and if that is the case this is a truly sad day.”

Unconfirmed reports stated that a prominent Aids researcher was on board flight MH17, along with four Dutch researchers.

Delegates from the Aids conference spoke at a prearranged event at the National Press Club in Canberra. Prof. Françoise Barré-Sinoussi opened her address with a tearful statement. She said: "Right now our thoughts are with their family. It will be a great loss for the HIV/Aids community.

"I had the privilege to work close with them ... If it is confirmed it will be a terrible loss for all of us. I have no word really to try to express my sadness, I feel totally devastated if it is confirmed."

Barré-Sinoussi received the 2008 Nobel prize in medicine for her role in discovering HIV, and is the president of the International Aids Society and international co-chair of Aids 2014.

Michel Sidibe, executive director of UNAids, tweeted: My thoughts & prayers to families of those tragically lost on flight #MH17. Many passengers were enroute to #AIDS2014 here in #Melbourne.

Michel Sidibé (@MichelSidibe) My thoughts & prayers to families of those tragically lost on flight #MH17. Many passengers were enroute to #AIDS2014 here in #Melbourne.

Melbourne Youth Force, one of the participant groups at the Aids conference, tweeted: “We are saddened to hear the news about MH17. Four Aids 2014 delegates were on board. Our thoughts are with their families and peers.”

US intelligence agencies believe the plane was shot down by a surface-to-air missile in eastern Ukraine.