http://www.bbc.co.uk/news/world-us-canada-13081831

UFO sightings have been made public by the FBI

Documents revealing new UFO sightings have been made public on the FBI's official database.

The previously classified records, which contain information of extraterrestrial encounters dating back 60 years, show eye-witness accounts of flying saucers and aliens.

Nick Pope used to be a government UFO investigator. He tells BBC Radio 5 live's Tony Livesey about lights in the sky and conspiracy theories.

For more Radio 5 live interviews, please visit the best bits page.

Read More In pictures: UFOs in the UK