The government is investigating a possible battery defect in the popular iPod Nano music player after reports that two overheated in Tokyo, scorching paper and a tatami mat, an official said Tuesday.
No one was injured, and there was no further damage, according to Hiroyuki Yoshitsune of the Ministry of Economy, Trade and Industry.
The latest problem follows a similar METI report in March about sparks shooting out of an iPod Nano, he said.
The government has been working with Apple Inc. to investigate the cause, and a defect in the lithium-ion battery is suspected in all three cases, he said. The iPods began to overheat while they were being recharged, he said.
He declined to disclose the manufacturers of the batteries and said it was unclear whether the same battery was being packaged in the product.
Apple Japan did not have immediate comment.
Yoshitsune said the two latest cases involved a model number MA099, which singed nearby paper this month, and a model MA005, which burned a tatami mat in January. Both players were twisted out of shape from the heat and became unusable, he said.
Other details weren't available.