SYDNEY (Reuters) – An Australian mining services company has fired up to 15 workers who performed an underground version of the Harlem Shake and posted it online, in a second incident of the Internet dance craze sparking safety concerns.

The workers were part of an overnight crew working at the Agnew Mine in Western Australia owned by South African miner Gold Fields Ltd. The workers were employed by Barminco, an Australia-based underground services company.

The 30-second video posted on YouTube shows a group of miners, some wielding tools and shirtless, performing the Harlem Shake, which typically begins with a one solo dancer who is quickly joined by others, often in costumes or with props.

Barminco, based in Perth, could not be reached for comment after a dismissal letter sent to the workers was obtained by the local newspaper, the West Australian, saying the stunt breached the company’s “core values of safety, integrity and excellence”.

But a spokesman for Gold Fields said the decision to fire the workers was taken by Barminco after the video was posted on YouTube last week.

“Underground mining has strict safety standards as there are accidents and fatalities. The Barminco management saw this as a breach of standards,” said spokesman Sven Lunsche on Monday.

The report came after the U.S.’s Federal Aviation Administration said it was looking into a mid-air, aisle performance of the convulsive dance by a group of college students on a packed flight due to safety concerns.

Frontier Airlines has defended its decision to allow the dance on the flight from Colorado Springs to San Diego, saying safety measures were followed and the seatbelt sign was off.

The sackings in Australia sparked an online debate with a Facebook page set up to call for the reinstatement of the “sacked WA Harlem Shake Miners”.

The workers told The West Australian that they were not endangering safety, pointing out that helmets were worn throughout.

The Harlem Shake is an electronic dance track by U.S. DJ Baauer – aka Harry Rodrigues – which was released last year with record label Mad Decent.

But it took off as a YouTube craze after a group of teenagers from Australia posted a video of their version of the dance which was replicated rapidly on the web, with up to 4,000 Harlem Shake video variations uploaded daily.

The craze has driven the song to top of the iTunes U.S. chart and third on the iTunes Australia list.