The U.S. government is warning about the potential dangers of fidget spinners, after receiving several reports of battery-operated versions of the toys catching fire.

In a safety warning posted on the U.S. Consumer Product Safety Commission (CPSC) website, the commission warns against charging the lightable toys overnight, noting there “have been some reports of fires involving battery-operated fidget spinners.”

Commission acting chair Ann Marie Buerkle said that, like any battery-operated product, fidget spinners should only be charged when someone can watch over the devices. They add that only the charging cord that came with the spinner should be used.

“It is important to use the charging cable that either comes with the fidget spinner or one that has the correct connections for the device as charging cables are NOT interchangeable,” she added in the statement.

As well, the commission warns that the spinners should be kept away from children younger than three years old, since small pieces in the spinners can pose a choking hazard.

Since choking incidents have been reported in children as old as 14, all children should be warned to keep the spinners out of their mouths.

“Fidget spinners can be fun to use, but consumers and companies should be aware of some of the safety concerns associated with this product,” Buerkle said.