Tokyo: Apple`s Japanese unit has offered to replace its first-generation iPod nano music player in the event of it overheating after reports of fires led to criticism from the government in Tokyo.
Apple confirmed "very rare cases of overheating" in the battery of the iPod nano sold between September 2005 and December 2006, which distorted the shape of the device or made it unuseable, the company said on its website.
It offered to replace affected units, adding that concerned customers using the first-generation iPod nano can now get the battery replaced, it said on its Japanese-language website.
The company noted the fault had been traced to a particular battery supplier, adding that other iPod nano models had no such recharging problems.
The Ministry of Economy, Trade and Industry has said the recharging problems caused 27 overheating incidents, including six fires, which left four people with minor burns.
On Sunday the ministry said Apple had separately notified it of 34 other "non-serious" overheating accidents related to the device. The ministry called Apple`s delay in doing so "truly regrettable".
The Japanese unit had put information on its website about the problems, including recommending battery replacements. However, the lack of prominence given to the warnings provoked criticism.
The company has since promised to improve its website. The ministry was yet to comment on the latest action by Apple.
Apple has sold about 1.8 million units of the 2005 iPod nano in Japan since September 2005.
The latest setback for Apple follows the launch of its iPhone 4, which has been dogged by reception problems linked to its new design and manufacturing issues that have led to the delay of the white version.