An Angry Neighbour has channelled their inner Liam Neeson in writing a threatening letter warning a dog owner to keep their pet inside.

The message was left in the mailbox in Perth by a furious resident demanding they keep their dog inside at night, before it took a sinister turn.

‘Sort out this problem or I will be taking the next step,’ the person writes. ‘And might I suggest you take this seriously as you don’t know who I am or what position I am in, or what I’m capable of.’

The letter starts in a mild manner, with the author apologising if the note has been placed in the wrong house. 

‘Firstly, I would like to offer my sincere apologies if this is not you. Now, straight to the point,’ it began.

‘No one wants or needs to hear a dog barking at 10 or 11pm at night. People have jobs, you know? Work they need to attend to get paid money to pay bills and their mortgage.’

The neighbour then begins to threaten the dog owner, saying they will get involved if the barking doesn’t stop.

‘Sort out this problem or I will be taking the next step,’ they wrote ominously, before adding they ‘don’t know who I am’ or ‘what I’m capable of’.

The author suggests they ‘don’t make me become a problem for you’ before offering a concise conclusion.

‘In summary, I hope it’s rather easy to get my point, KEEP YOUR DOG INSIDE AT NIGHT,’ they wrote. ‘I AM SICK OF IT’.

Comments were mixed with some laughing at the ridiculousness of the letter while other agreed incessant barking at night is extremely frustrating.

‘Thats going to be awkward for the dog owner when they look at all the neighbours with paranoia,’ one person replied.

‘Buy a chainsaw, and run it full tilt all day outside of the noise curfew hours. That might take the edge off the dog barking,’ another suggested.

‘As someone who has lived through the experience of neighbours who don’t train their dogs – I can relate to the frustration in this note!’ a Facebook user commented.’