Aussie Jihadist
Abdullah Elmir from Sydney, aged 17, appeared in a YouTube clip in October alongside Isis fighters, threatening Tony Abbott and any nation that stood in the way of Isis. slack-redir.com

Two Australian brothers who have flocked to join the Islamic State [IS] in Syria have been described as "unfit", "obese" and "not fit to fight".

An Australian-Muslim community leader, Dr Jamal Rifi, said that two of the four brothers from Sydney were weighed more than 140kg (308lb, 22st) were unable to run let alone fight for the jihadi cause.

The brothers, son of Lebanese immigrants, told their mother last week that they had reached Syria in search of "paradise", despite telling her that they were travelling to Thailand for a holiday.

Rifi added that it would be embarrassing for the brothers to eat the food of the jihadists and fight alongside them as the large brothers "can't even run on the field".

"They're definitely not fit to fight, they don't have any knowledge of how to fight. They would be used for a propaganda video the same way as we saw with Abdullah Elmir," said Rifi, referring to the Australian Ginger Jihadist at the centre of one of the terror group's recruitment videos.

"They didn't show any signs of radicalisation. They were good boys, which is why their mother is so shocked,'' he added..

The four brothers who travelled to Syria are aged 17, 23, 25 and 28 respectively.

All are devout Muslims who regularly attended prayers at mosques and it was reported that their amateur attempts to join the jihadi cause were hampered from the beginning when they missed their flight out of Australia, according to Australia's Daily Telegraph.

It is believed that all four were radicalised and Australian intelligence authorities are now working to identify the figures who influenced the youths.

More than 60 Australian citizens are currently fighting with ISIS, the splinter group Jabhat al-Nursa and other groups in Syria and Iraq. Another 20 have returned after fighting in Iraq and Syria and are living within the community.

A recent Isis video featured white Sydney-born Muslim convert Abdullah Elmir, 17, calling himself 'Abu Khaled from Australia' flanked by other militants.

Speaking directly to the camera, the jihadist told Western leaders their efforts to defeat Isis would fail, adding that the terrorists aim to raise their black flag over Buckingham Palace and the White House.