The IPCC has criticised the Chief Constable of South Yorkshire Police, David Crompton, about emails in which he says the Hillsborough campaigners are not telling the "truth".
The IPCC has written to Mr Crompton to express concerns about the email, which he wrote in relation to plans for the force's handling of the publication of the Hillsborough Independent Panel report.
In January 2013 the Police and Crime Commissioner of South Yorkshire, Shaun Wright, wrote to the IPCC when he was made aware of the email. It was one of many supporting documents released under Freedom of Information Act.
More top news
Chris Gunning was walking his dog along the beach when it ran onto the mud flats.
The 46-year-old was arrested on suspicion of membership of a proscribed organisation and malicious communications.
What does the weather have in store for the next few days?