The safety of so-called hoverboard devices has been a hot topic of late, and now the U.S. Consumer Product Safety Commission has weighed in on the issue.

The independent U.S. regulatory agency has issued an official warning to manufacturers, importers, and retailers of self-balancing scooters: Get your devices certified, or risk civil and criminal penalties. In a letter, the CPSC urged hoverboard makers and sellers to ensure their devices comply with new safety standards, and voluntarily take them off the market until they can be deemed safe by an independent testing firm.

The commission said it has received reports from consumers in 24 states of 52 self-balancing scooter fires between Dec. 1, 2015 and Feb. 17, 2016. Together, these incidents resulted in more than $2 million in property damage, "including the destruction of two homes and an automobile," the agency said.

"We believe that many of the reported incidents, and the related unreasonable risk of injuries and deaths associated with fires in these products, would be prevented if all such products were manufactured in compliance with the referenced voluntary safety standards," the CPSC wrote.

Going forward, all self-balancing scooters sold in the U.S. that do not comply with the new hoverboard safety standards will be considered "defective," the agency said, adding that it may seize uncertified devices being imported into the U.S., or recall products already on shelves.

"CPSC staff will follow-up as appropriate in the future to ensure that the firms are meeting their obligations in this area," the agency said.

The crackdown on hoverboard safety comes after Amazon in December pulled a number of hoverboards from its site over safety issues. The U.K.'s consumer protection agency has seized some 15,000 unsafe hoverboards based on issues with the plug, cabling, charger, battery, or cut-off switch. A number of U.S. and European airlines, meanwhile, have banned the devices from carry-on and checked luggage, claiming the scooters' lithium-ion batteries are often mislabeled.

This article originally appeared on PCMag.com.