Pentagon reveals secret UFO research unit

The Pentagon has just admitted it ran a secret UFO investigation programme for five years until 2012. The Department of Defense's "X-Files" operation, was known by the less catchy title of the Advanced Aviation Threat Identification Program, was closed after a change in funding priorities, it said. But the remarkable revelation has raised more questions than answers, including whether the programme has been completely shut down, or just covered up further. Let's go now to Nick Pope who used to run the UK government's research project on UFOs.