There are some TikTok trends that are relatively harmless—lip-syncing and dance moves, for example. However, when they involve something harmful, like fire, that’s where you can run into trouble.

Typically, it’s the younger generation who falls for the social media trends that can be damaging. (Let’s not forget the Tide Pod Challenge or the Salt and Ice Challenge that was causing harm left and right.) Now? It’s the “fractal wood burning” challenge that caused the death of a couple.

The couple was older this time—Tanya Rodriguez, 44, and James Carolfi, 52, were killed while practicing fractal wood burning in the garage of their home in Wisconsin on April 6. The deaths were ruled to be “accidental” since no foul play was involved.

When investigators looked into the case, they were originally baffled by what happened. The house was burned and the bodies were found in the garage after the flames were put out. That’s why foul play was initially suspected. However, an autopsy revealed it was indeed the TikTok trend at work.

“Foul play has been ruled out and the deaths are found to be accidental in nature and believed to be caused by electrocution from fractal wood burning,” said Chief Deputy Chad Billeb.

The dangers of fractal wood burning occur due to the combination of high-voltage electricity and a chemical solution that allows you to engrave designs into slabs of wood. The process was initially discovered back in 1777 by German physicist Georg Lichtenberg while he conducted static electricity experiments. The designs are commonly signs of being struck by lighting, like tree branches, lightning bolts or ferns.

Recently, hashtags like #fractalburning and similar on TiKTok have been building up millions of views. People are often attracted to the seemingly cool veins that spread across the wood. However, there have been dozens of fatal fractal wood burning cases on top of this Wisconsin couple. In fact, since 2016, around 33 people have died from the wood-burning method.

In the case of Rodriguez and Carolfi, the power supply was determined to be a disassembled microwave and the couple had accidentally electrocuted themselves. A fire then burned the home after the two had already died. “Taking advice from YouTube or any other social media site in order to do a craft … is not safe when you’re dealing with electricity,” Billeb said.

Moral of the story: Don’t participate in TikTok trends—especially ones that involve fire.

To learn more about fractal wood burning and the harm it can cause, check out the video below.

Have you heard of fractal wood burning before? Do you know anyone who has attempted it?