George Michael’s Australian ex-boyfriend has been arrested for smashing up the late singer’s palatial London house, with video showing him being detained by four police officers.

Fadi Fawaz, who was left out of the late Wham! singer’s $172 million will, was arrested on aggravated criminal damage allegations.

Neighbours alerted officers after seeing him standing on the roof of Michael’s $9 million property, which he has refused to leave against the wishes of Michael’s family.

Video shows him wearing a white shirt, while in handcuffs with four police monitoring him.

The Brisbane-raised Fawaz, 46, was accused of extensive damage.

“I’ve never seen anything like it,” a source told The Sun in London.

“Every fixture and fitting, every door and window, everything George left in there — it’s all completely destroyed.

Even the toilets and sinks have been smashed. There’s major damage to the walls and even the ceilings.”

The damage was so bad, there were reports that water had been gushing out the front door.

“This can’t have happened in just one night, he must have been systematically smashing the place up for a long time,” the source continued.

A Met Police spokesman said: “Police were called on Tuesday, 23 July at around 7pm to a report of a man seen on the roof of an address.

“Officers attended and the man was no longer on the roof but inside the address, which had extensive damage.”

Last year it emerged the Wham! star did not leave anything for Fawaz in his £96.7 million ($A172 million) will.

Michael’s family want Fawaz out of the house, near Regents Park in central London, but he is refusing to leave. He has vowed he will only leave “in a box”.