Microsoft is recalling 2.25 million AC power adapters in the U.S. because of potential for fire or electric shock. The AC power cords being recalled were sold with the Microsoft Surface Pro, Surface Pro 2 and Surface Pro 3 computers before March 15, 2015, the Consumer Product Safety Commission said.

The recall also covers the power supply units with AC power cords sold as accessories before March 15, 2015.

Microsoft will issue a free replacement. The CPSC noted that close to 190,000 power cords were also sold in Canada.

Microsoft earlier issued a voluntary recall of the affected power cords. CPSC said that Microsoft had received 56 reports of AC power cords catching fire after overheating, and five reports of electric shocks.

A replacement can be requested through Microsoft's support site.

The recall does not apply to AC power cords for Surface RT, Surface 2, Surface 3, Surface Pro 4, and Surface Book. It also does not apply to the Surface Pro 3 tablets sold after March 15, 2015.