Nearly seven years after the terrible events of that September day, the US authorities are due to publish the final report on a third tower that also collapsed on 9/11. Unlike the Twin Towers, this 47-storey, 610-foot skyscraper was not hit by a plane. The official explanation is that ordinary fires were the main reason for the collapse of Tower 7. That makes this the first and only tall skyscraper in the world to have collapsed because of fire. Yet despite that all the thousands of tonnes of steel from the building were carted away and melted down. The way official bodies have investigated Tower 7 at the World Trade Center has made some people think they're hiding something. Its destruction was never mentioned in the 9/11 Commission Report. An inquiry by the Federal Emergency Management Agency said the building collapsed because intense fires had burned for hours, fed by thousands of gallons of diesel stored in the building for emergency generators. But its report said this had only a low probability of occurrence" and more work was needed. That was in May 2002. The task has now fallen to the National Institute of Standards and Technology (NIST) based at a sprawling campus near Washington DC. For more than two-and-a-half years, scientists there have been studying Tower 7. The officials have been criticised for being slow and even of being frightened to publish. Steven Jones, a former physics professor at Brigham Young University, who has become [a] leading academic voice in the movement, first watched a video of the collapse of Tower 7 in the spring of 2005. But when he did, he said he was taken aback as a physicist.