Various news reports today mention that al-Qaeda in the Arabian Peninsula is claiming responsibility for the crash of a UPS cargo plane at Dubai on September 3, as well as the more recent incidents involving parcel bombs.

The Boeing 747 aircraft had taken off from Dubai 45 minutes before it crashed and was attempting to return after the pilot reported smoke on board. 

However, US officials are sceptical about al-Qaeda's claim, saying that the sound of an explosion on board would have been picked up by the cockpit voice recorder – and there is no evidence of that.

Could it have been an incendiary device instead of a bomb? Again, US investigators seem doubtful. CNN says a review of the cargo manifest found the plane was carrying a small number of packages that originated in Yemen, but it quotes an official as saying "They (investigators) have a basic idea of what part of the plane the fire started and these were nowhere near there."

Investigations so far have focused mainly on some lithium batteries that the plane was carrying.

Posted by Brian Whitaker, 6 November 2010.