A teenager has been arrested for allegedly planning a terrorist attack in Sydney

Photo: Paul Miller/ Getty.

The federal police have arrested an 18-year-old Macquarie Park man for allegedly planning a terrorist attack in Sydney.

Police believe the man was acting alone, and was in the process of acquiring a firearm.

Police say the arrest is not connected to the raids undertaken in Melbourne this morning, which was linked to the five men arrested for trying to take a tinnie to Indonesia to join ISIS last week.

“As of today nine imminent attacks have been prevented,” said deputy commissioner Catherine Burn.

She said it was unfortunate that the group of people involved in these foiled attacks are getting “younger and younger”.

“We can’t do this alone, we all have to work together… particularly the mums and dads, brothers and sister, friends and colleagues,” she said.

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