UPDATE 9.50am: NSW police rule out planking as cause of serious accident which left a 20-year-old man with horrific head injuries, while Queensland police charge three men who planked on the roof of a car.

Police in Toowoomba have charged three men in their early 20s with public nuisance for allegedly riding on top of a car in the city's CBD at 10pm last night.

A police spokeswoman said the threesome had been issued with on the spot infringement notices.

The female driver, 20, will face court on June 15, for a dangerous operation of a motor vehicle charge.

Toowoomba District Acting Inspector Jim Fenton said he was in disbelief.

"We would question their level of intelligence and due regard to self-preservation,'' Acting Insp Fenton told the Toowoomba Chronicle.

The internet craze of "planking'' tipped over into tragedy with the death of a young man who plunged seven storeys from the balcony of a Brisbane apartment building on Sunday.

Acton Beale, 20, is believed to be the first person killed while taking part in the fast-growing global fad, in which people have photos of themselves taken while lying face-down in a public place and post the results on the internet.

Meanwhile another young man may never recover from horrific head injuries after he fell from the back of a car while skylarking with friends.

Simon Hallam, a plasterer from Inverell in northern NSW, suffered serious injuries on Monday night when he fell heavily from a fast-moving car.

Police said witnesses told them Mr Hallam was attempting to "plank" on the boot of a sedan moments before he fell.

He is now in an induced coma in an intensive care unit.

But police have now revealed the man was standing at the time of the accident, not planking as suggested by early witness reports.

A spokeswoman for the Tamworth Base Hospital where Mr Hallam has been transferred to said he remains in a serious, but stable condition.

Inverell police said Mr Hallam was on the boot of a car in Henderson Lane, shortly before 9pm, when the accident happened.

"We have spoken today with witnesses who have reported the young man was in fact 'planking', or similar too it,'' a police spokesman said yesterday.

Doctors at Newcastle's John Hunter Hospital have told the family they do not know if Simon will ever recover from the accident.

"They have told us it's just day-by-day, that's all we know,'' distraught father, Terry Hallam, said.

Mr Hallam said his son's accident should be a warning to others.

"You do these things to be noticed, to get attention. Well look at the attention Simon's getting from the doctors and nurses, and he doesn't even know about it,'' Mr Hallam said.

Planking attracted national headlines when Brisbane man Acton Beale fell seven storeys to his death off a balcony railing on Sunday.

Mr Hallam blamed social networking sites for the rise in competitive behaviour among young people.

"The internet and Facebook, they're just dreadful things, they encourage this sort of behaviour,'' he said.

"And young ones don't think about consequences of their actions.

"They think it's fun now so they do it, with little thought for what could happen, like this.''

With an alarming increase in the amount of injuries caused by the craze, the Ambulance Service of NSW yesterday released a warning specifically aimed at people considering "planking".

"Don't take unnecessary risks and use common sense as serious injury may result in a "planking'' stunt that goes wrong. These stunts can also lead to hospitalisation, great embarrassment or even death,'' the statement said.

An Inverell man, 19, has been charged with dangerous driving causing grievous bodily harm, and is due to face court next monthnte.

With authorities increasingly worried about the dangerous risks being taken by plankers a new group is gaining popularity as a safer form of the "sport".

"Teapotting" asks people to strike a teapot pose, raising an arm to form a spout and bending the other to make the handle.

The trend has attracted a short but stout 2100 fans since it was created by Victorian teachers on Monday.

Mortlake College teacher, Olivia Campbell, 23, said they were now having discussions with organisers of Australia's Biggest Morning Tea, scheduled for next week, to link the latest social media craze with the cancer research fundraiser.



"We're trying to come off as a positive version of planking,'' she said.

Despite the safer teapotting message, at least one person has been snapped standing on a horse's back in the pose.

-with AAP and Clementine Cuneo

Originally published as Trio charged over planking craze