Flaws in batteries caused the fires in Samsung Electronics' Galaxy Note 7, which led to a worldwide recall and production halt of the smartphone, results of tests conducted by South Koreas product safety watchdog show.
The state-run Korean Agency for Technology and Standards found no problems in the smartphone's hardware design or software, Yonhap news agency reported on Monday.
These conclusions are similar to the probe result announced by Samsung Electronics last month.
"Our investigation concluded that the batteries were found to be the cause of the Note 7 incidents," Samsung had said.
In a test conducted by the Korean Agency for Technology and Standards, it was found that electrodes of batteries installed in the Galaxy Note 7 were damaged, while some batteries missed insulation materials, South Korea's Ministry of Trade, Industry and Energy said in a release.
"Problems in the batteries were found to be highly likely the cause of the fires, but we found nothing unusual in the smartphone itself," the report said.
Battery manufacturers have failed to deal with safety problems as their battery was a newly advanced type in terms of capacity for the high-end smartphone, the report added.
The Galaxy Note 7 was launched worldwide in August last year, but a series of fires led Samsung Electronics to discontinue the smartphone in October after recalling millions of the devices throughout the world over safety concerns.
The government said it would tighten safety guidelines on lithium-ion batteries and smartphones in order to prevent further cases.