'Organisational arrogance' on the part of different crime agencies hampered the probe into Madeleine McCann's disappearance, according to the author of a previously unpublished report on the investigation.
Jim Gamble told the Guardian: "Each one thought that their agency would bring the best to bear on this. We were all guilty."
He also told Sky News that different agencies trying to make their mark "created a sense of chaos and a sense of competition".
Mr Gamble, the former head of the Child Exploitation and Online Protection Centre, said this had also damaged the relationship between British and Portuguese investigators, leading to further difficulties.
More top news
A vicar who was diagnosed with HIV after being attacked two years ago has created a powerful video to share her story with her congregation.
A man miraculously survived being shot near his home with a sawn-off shotgun when his mobile phone took the brunt of the blast.
A video of basketball player's daughter has gone viral after the cute two-year-old turned on the charm to eclipse her superstar dad.