Finding the must-have Christmas present of 2015 may soon be impossible, but not because it's sold out. The hoverboard, or self-balancing scooter, is at the center of a dozen fire investigations by the U.S. Consumer Product Safety Commission (CPSC), and in the U.K., hoverboards have been held at customs for safety reasons.

Several airlines have banned hoverboards due to safety concerns. Amazon has not only discontinued the sale of these popular items; the online retail giant has also advised consumers in the U.K. to dispose the items at a designated recycling center.

The CPSC has 12 open hoverboard fire investigations, the agency announced on Twitter. It stated the incidents have occurred in 11 states, with at least 40 reported injuries. The commission is currently testing hoverboards.

A hoverboard caught fire while it was charging in the San Francisco Bay Area city of Brentwood Tuesday. The family was home at the time of the fire, which occurred when the 15-year-old sister of Aliyah Denny stepped on the scooter when it was charging. "It almost exploded in her hands. It basically started to burn up the wall toward the entrance of our house," Denny said to local station KPIX 5. No one was injured in the incident, but the family is seeking a refund from Amazon.

A specific hoverboard brand was not mentioned, but KPIX 5 reported the family paid $235 for the scooter.

Amazon sent letters to consumers in the U.K. to throw away their hoverboards at approved centers that can handle electrical items, BBC reported. "We regret the inconvenience this may cause you but trust you will understand that your safety and satisfaction is our highest priority," Amazon wrote in an email to customers who purchased a hoverboard with a "noncompliant U.K. plug."

Customers can get a refund within three days from Amazon. Customers who purchased a hoverboard with a compliant plug received safety instructions and an option to return the scooter, BBC reported. discontinued the sale of all hoverboards while Amazon has halted the sale of several major brands, including PhunkeeDuck, Swagway and IO Hawk. Amazon is currently selling Jetson hoverboards and Razor Hovertrax hoverboards. Target currently sells Swagway and Razor Hovertrax hoverboards online. Walmart sells Razor Hovertrax hoverboard online and in-store.