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Australia police launch massive 'counter-terrorism' raids

Police in Melbourne, Australia.
Robert Prezioso | Getty Images

Hundreds of heavily armed police raided homes in Sydney and Brisbane before dawn on Thursday, launching a large-scale Australian "counter-terrorism operation" just days after the country raised its national terror threat level to high for the first time.

Australian police said the raids were focused on a dozen suburbs in west Sydney, while local media said operations were also taking place in the Queensland city of Brisbane.

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Last week, Australia raised its terror threat level to 'high', citing the likelihood of terrorist attacks by Australian citizens radicalized in Iraq or Syria, despite stressing there was no knowledge of a specific threat.

Australia, which is due to host the Group of 20 Leaders Summit in Brisbane in mid-November, is concerned over the number of its citizens believed to be fighting overseas with Islamist militant groups.

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Up to 160 Australians have either been involved in the fighting or actively supporting it, officials said. At least 20 are believed to have returned to Australia and pose a national security risk, the head of the country's spy agency said when raising the threat level last week.

Prime Minister Tony Abbott, highlighting the risk of homegrown militants returning from the Middle East, pledged on Sunday to send a 600-strong force as well as strike aircraft to join a U.S.-led coalition fighting Islamic State militants in Iraq.

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Police would not comment on the number of arrests that had been made or the number of security forces involved, but local media said that with up to 600 officers taking part, the raids could be Australia's largest ever.

Australia had been at the "medium" alert level since a four-tier system was introduced in 2003. A "high" alert level is used when officials believe an attack is likely, while a "severe" level means they believe an attack is imminent or has occurred.