A family caught up in Australia’s biggest counter-terrorism operation is reportedly set to launch legal action, claiming to have been unfairly targeted.

The brothers, aged 15 and 14, and their mother have told Fairfax Media they were mistreated as police took 12 hours to search their home in Sydney’s southwest but found nothing.

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Using the name Mohamed, the older of the brothers says he was woken at 4.30am by men in balaclavas who bashed the door in and dragged his mother out of bed without giving her a chance to cover herself.

Mohamed claims she was also punched because she tried to resist, and that he and his brother were handcuffed during the ordeal.

“They bought in dogs to smell the place, they bought in metal detectors, they scratched the doors, they dug up the backyard, they looked through all the books and they found nothing,” he told the Sydney Morning Herald.

“Even if they found one thing, they would have charged us.”

The paper says the family of three will launch a civil suit in the NSW Supreme Court this week.

Their home was one of 16 raided by state and federal police before dawn on September 18, but they were not detained or charged and they still have not been told why they were raided.