A three month old iPhone has reportedly combusted in a user’s pocket in Finland. According to the report, the iPhone was safely stored in his pants back pocket when smoke started to appear. The phone was ripped from his pocket and thrown to the ground. The whole incident was caught on a security camera.
The iPhone, which looks like an iPhone 3GS rather than the later iPhone 4 or iPhone 4S models, ended up in a bad way. We have heard a similar story recently when an iPhone started to behave in the same way when on an Australian aircraft. After investigation, it was found to be caused by a third party battery replacement. This time however the iPhone is said to be only three months old and it's unknown what may have caused it.
While there have been legitimate battery problems in everything from laptops to mp3 players from Apple and other manufacturers, it's impossible to count out publicity stunts or other possibilities until more information is known.