Kangaroo fires up the internet flexing muscular chest

A huge kangaroo has become an Internet sensation after being filmed in an outback Australian creek flexing its muscular chest.

The boomer was caught by a photographer in a creek south of Perth.

More than 600 people commented on the bizarre occurrence, with many people expressing disbelief at the animal's physical shape.

'Wow, what a brilliant powerful roo. Look at his paws and claws. Have you ever seen a roo that big,' one social media user wrote.

For a laugh one post took the animals view, writing : 'Are you right mate!! I'm trying to have a bath here, fair dinkum.'

Multiple photos of the rare event were shared to Facebook and quickly attracted more than 850 likes and nearly 3000 shares.

The kangaroo was aware that its splash in Boodjidup Creek, in the Margaret River region, was being observed, and seemed to glare at the human intruders.

The photographer was accompanied by a dog, and the marsupial kept a wary eye on the canine throughout the encounter.