Google-owned Fitbit has recalled more than a million of its Ionic smartwatches following reports that overheating batteries had caused burn injuries, the U.S Consumer Product Safety Commission (CPSC) said on Wednesday.

The Consumer Product Safety Commission (CPSC) in the US said in a statement that at least 115 people in the US — and 59 globally — have reported an overheating battery on the device.

There were 118 reports of burns, with two reports of third-degree burns and four reports of second-degree burns.

The lithium-ion battery in the Ionic smartwatch with the model number FB503 can overheat, posing a burn hazard.

There are around 1 million of these smartwatches in the U, and in addition, about 693,000 were sold internationally.

“Customer safety is always Fitbit’s top priority and out of an abundance of caution, we are conducting a voluntary recall of Fitbit Ionic smartwatches,” the company said in a statement.

“We received a very limited number of injury reports – the totals in the CPSC announcement represent less than 0.01 percent of units sold – of the battery in Fitbit Ionic smartwatches overheating, posing a burn hazard. These incidents are very rare and this voluntary recall does not impact other Fitbit smartwatches or trackers,” the company added.

Fitbit is refunding the wearable device to the tune of $299.