A report claims at least one Mac that used a faulty Sony battery caught fire this year.

According to the Japanese government, the Mac - which used one of the 1.8 million batteries now being recalled by Apple - overheated and caught fire in April this year. The user suffered a burnt finger. Apple has confirmed nine similar cases in the US.

The government also confirmed that at least two Dell notebooks also suffered the problem, which is caused by a batch of faulty batteries from Sony.

Japan's trade ministry has ordered Apple Japan to report its findings on the matter by 5 September, or face punishment under consumer safety laws. Sony and Dell have also been asked to report on the problem.