Rockhampton, Australia - It all started when Monica Green noticed that items were being moved about in her home.

At first she didn't think anything of it. After all, she had three children, and one of them could easily be the culprit.

But when she noticed that her security camera had been disabled, she knew something was off.

A coincidence? Unlikely. But Green remained calm. Again, it could have been her kids.

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When she returned from a doctor's appointment one day, she couldn't believe what she saw: the air conditioner was running at full speed, the television was on, the back door was open, and someone had used the oven to cook chicken nuggets.

The Australian woman immediately called the police. Arriving at the scene, officers found the roof hatch in her ceiling was partially open.

They climbed up and made a shocking discovery: someone had been living in the attic!

According to Monica, the intruder had stolen her keys and stood on her car to reach the roof hatch. To be safe, she has since changed the door lock.

"What has this person been doing in my house when I'm not home? Were they trying to harm me or my kids?" said the mother-of-three, who has since found herself "shaking at the smallest noise."

The police found several clues that someone must have indeed been living in her attic for weeks. But who exactly was hiding up there remains to be investigated.

Monica Green has been living in a constant state of fear since the incident. "Did they want one of my kids? Were they going to come down at night and murder us? There's all these unknown questions rolling around in my head," she said.

The police are currently tracking down the intruder.