A mom and her three young children have been left terrified and shaken after discovering that an intruder had been living in the attic of their home for three weeks undetected.

Monica Green, who hails from Queensland, Australia, had begun to notice some strange occurrences around her home, but initially blamed the anomalies on her children and a faulty home security system.

However, on one particular day, the series of disturbances became simply too marked to ignore, and so Green called the police after returning home early from a doctor's appointment to find her house completely different to how she left it.

A kitchen [[imagecaption|| Credit: Pexels]]

Per the New Zealand Herald, Green returned home to find the back door of her house wide open, the air conditioning and television switched on and a half-cooked plate of chicken nuggets left on the oven.

When the police arrived, they reportedly uncovered evidence of a person living in the ceiling after spotting a manhole cover in the ceiling partially open.

"I felt violated. I felt like my personal space had been invaded. I felt shocked, terrified, scared," Monica Green told the Courier Mail.

“I felt like it was something out of a horror film,” she said, per news.com.au.

A widow open on a roof [[imagecaption|| Credit: Pexels]]

“Why was he in the roof? What was his intentions? Was he here to harm us? Was he here to steal one of my kids?

“I’m meant to be the one that protects them and I feel like I’ve failed.”

Jason Milner of Queensland Police described the situation as “certainly unique."

“It’s not a usual break and enter occurrence,” he added.

She believes the individual in question may have broken into her house after stealing her keys, and has since changed the locks. The incident left Green and her family shaken.

"What has this person been doing in my house when I'm not home? Were they trying to harm me or my kids? 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.

"I'm finding myself constantly shaking at the smallest noise. I'm triple-checking all my locks now before I go to bed. I spent the night in the house last night with family here, but being alone in the home scares me."

Terrified woman discovers stranger living in her attic after noticing objects mysteriously moving around