150 Australians Among Hundreds of Western Fighters in Middle East, Official Says

An estimated 150 Australians have left their homes down under to take up arms with extremist groups in the Middle East, Australian Foreign Minister Julie Bishop said Wednesday.

"I had intelligence briefing from agencies this [Wednesday] morning and [the] best estimate is that there are about 150" fighters from Australia who either have fought or are fighting "with opposition groups in Syria and beyond," Bishop told ABC radio, calling the number "extraordinary." "In Syria, it seems that over a period of time they have moved from supporting more moderate opposition groups to the more extreme, and that includes this brutal extremist group ISIS."

ISIS refers to the Islamic State of Iraq and Syria, the U.S.-designated terror group, formerly allied with al Qaeda, that grew during the Syrian conflict and is now waging war in Iraq.

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Bishop also became the latest high-level official from Western governments to express "deep concern" about the potential for scores of fighters, beyond wreaking havoc in Syria and Iraq, to return home and attack their homeland. When asked if the Australian fighters represented a "clear and present danger," Bishop said, "Of course."

"We are concerned that Australians are working with them [ISIS], becoming radicalized, learning the terrorist trade, and if they come back to Australia, of course it poses a security threat," Bishop said. "I've canceled a number of passports on the advice of intelligence agencies."

Bishop's cautionary words came the same day British Prime Minister David Cameron told lawmakers there that the British government estimates there are "around 400" people from the United Kingdom that have "taken part in fighting with ISIS," noting that that estimate is based on information in Syria and doesn't include Iraq "where we have considerably less information."

"The estimates are now this is a greater threat to the U.K. than the return of foreign jihadis or fighters from Afghanistan or Pakistan region, and we need to make sure we are doing everything we can to keep our country safe," he said.

Across the pond, an estimated 100 Americans have also left the states to join the fight, according to a person briefed by the FBI, in addition to another estimated 400 from Denmark. Germany's domestic security services estimates 320 of its citizens have traveled to Syria to fight with or support Islamist rebels. Between 76 and 300 others have come from Belgium and possibly more than 400 from France, according to a December 2013 report from The Washington Institute for Near East Policy.

The U.S. Department of Justice announced Wednesday that two U.S. citizens, both living in Texas, had been arrested and charged with terrorism-related crimes. One of the men planned to travel to Syria to join a jihadi group there, believed to be ISIS, prosecutors said in court documents.

Top U.S. intelligence and law enforcement officials have been sounding the alarm about Americans heading to Syria and potentially returning home to cause mayhem for months. ABC News reported in January that the FBI was already monitoring dozens of people who had fought in Syria and returned to the U.S.

FBI Director James Comey told ABC News in May that his organization aimed to make sure the "coming Syria diaspora" does not turn into a "future 9/11."

In an Op-Ed in The Washington Post today, former U.S. Ambassador to Iraq Ryan Crocker said as many as 2,000 ISIS fighters hold Western passports.

"This is global jihad, and it will be coming our way," he wrote.

(Australian ABC is not affiliated with the U.S.-based news outlet ABC News.)