Apple Inc. has until the end of this month to report to the Consumer Affairs Agency on its efforts to warn users that some iPod Nano music players may overheat and catch fire.

The agency asked Wednesday that the report be submitted by Aug. 31, official Kiyomu Taki said Thursday.

Apple updated its Japanese Web site earlier this week to say it will offer replacements for music players that overheat, following calls by the government to take measures to prevent the devices from catching fire. The company had previously only offered to change the device's battery.

Apple has also contacted iPod those owners who registered their e-mail addresses, warning of the dangers, the Ministry of Economy, Trade and Industry said in a separate statement Thursday. METI said Apple responded Wednesday to its earlier request for information, detailing additional safety measures.

Six incidents involving the 2005 model Nano catching fire while being charged have been reported to the government since 2008, METI spokesman Hiroshi Miyashita said last month.

This is the second time the government has warned that the iPod Nanos may pose a fire hazard. In 2008, it said there had been at least three fires linked to the music players since 2005 because of malfunctioning batteries. Apple said at the time there were "very few" such reports and that there were no reports of incidents with other Nano models.