Mysterious Iranian Explosions

A report earlier this month said there was an explosion at an Iranian military base near Iran's capital of Terhan, killing a reported 27 guard members.  Now there has been a second explosion at the city of Isfahan, which is where a key nuclear facility is located.  Iranian officials said it was a military drill not related to the nuclear facility, but other reports included a gas station explosion and a training accident.  What is for certain is that, once word of the explosion reached Israel, the Fars news agency quickly removed the story.