An Australian family has been hit by both Malaysia Airlines tragedies after losing four members on board the MH370 which disappeared in March and now from the doomed MH17 struck down by a missile over war-torn Ukraine.

Queenslanders Irene and George Burrows are still mourning the tragic loss of their son Rodney and his wife Mary who were on board the MH370 which vanished from radar screens in March. Dubbed the greatest aviation mystery of all time, four months on and no debris from the plane has ever been recovered.

Now they are having to grieve for their step-granddaughter Maree Rizk and her husband Albert, who are among the 28 Australians confirmed dead in flight MH17. The Melbourne couple were returning from a European holiday on board the ill-fated Kuala Lumpur-bound flight from Amsterdam.

There were 298 passengers in total including 189 Dutch nationals, 44 Malaysians, and nine Britons who died. Eighty children also lost their lives when the plane was allegedly shot down by pro-Russian insurgents in Ukraine.

Twelve Indonesians, four Germans, four Belgians, three Filipinos, one Canadian and one New Zealander have also been identified. The nationalities of a further 4 passengers are yet to be confirmed.

Rizk's stepmother Kaylene Mann, also the sister of Rodney Burrows was too upset to speak publicly about the second loss to hit the family.

Speaking at a press conference on Friday, a sombre Australian prime minister Tony Abbott, joined world leaders in calling for a swift investigation into the shooting down of the Boeing 777. He said: "We grieve for all but we particularly grieve for and pray for the Australians who have lost their lives.

"I want to say to the Australian people that as far as I am concerned when you have a situation where Russian-backed rebels appear to have killed Australians using, it may well turn out to be Russian-supplied heavy weaponry, Australia takes a very dim view indeed and we want the fullest possible investigation."

German Chancellor Angela Merkel, who backs a ceasefire in Ukraine while investigations are carried out into the alleged downing of the plane, said: "Our thoughts are with the relatives of those who were on board MH17. I have called Dutch prime minister Mark Rutte to assure him that our thoughts are with the Dutch at this moment.

"What is important now is for an independent investigation to take place as soon as possible. For that, a ceasefire is needed, and then it is of course crucial for those responsible to be brought to justice."

Speaking after chairing a Cobra meeting, David Cameron said "It is an absolutely shocking incident; it cannot be allowed to stand. Until we know more, it's not really possible to say much more, but we'll be working very hard to get to the bottom of this."