Yes, the iPhone is smoking hot - but literally?

SAN FRANCISCO - Apple's iPhone is the world's hottest smartphone - and one iPhone in Australia appears to be the hottest of the bunch as it spontaneously began smoking last week.

Regional Australian airline Regional Express described the "mobile phone self combustion" in a statement, saying an iPhone belonging to a passenger started glowing red and expelling a "significant amount of dense smoke" after a flight from Lismore, Australia, landed in Sydney on Friday.

A photo accompanying the statement showed the shattered, warped back of a recent-model black iPhone.

The airline says a flight attendant extinguished the glow and nobody on the plane was hurt. Regional Express reported the incident to authorities in Australia. Apple says it will cooperate with any investigation.

Australia's Transport Safety Bureau (ATSB), which took possession of the iPhone, said it was investigating the incident.

"We are investigating, it's quite early on in the investigation," a spokesman for the ATSB told AFP. "However, we do have the phone, it's in our custody, and we will be undertaking a technical examination of it. We will be interviewing directly involved parties and also in our technical examination of the phone we are going to be consulting with the manufacturer as well."