A chief constable has defended his force's handling of child sex allegations against former prime minister Sir Edward Heath.

Mike Veale, who leads Wiltshire Police, wrote an open letter to the public to "set the record straight" about the investigation.

"When I took on this investigation I knew it would attract intense scrutiny. I also recognised it could potentially damage confidence in Wiltshire Police," he said.

He described the former Conservative prime minister, who died at home in Salisbury in July 2005 aged 89, as an "extremely prominent, influential and high profile person".

"The decision to undertake this incredibly complex and challenging investigation was not taken lightly particularly knowing, or at least expecting, that we would be placed under intense scrutiny," he said.

The police probe, named Operation Conifer, began in 2015 after claims against Sir Edward surfaced.

Mr Veale said: "Over the last few weeks particularly, there has been much speculation about this case.

"Whilst it is not commonplace for us to comment on a live ongoing criminal investigation I really am very concerned and profoundly disappointed about the impact of this speculation on the public's confidence in the police, the potential prejudicial impact upon a live criminal investigation, not to mention the confidence of persons who have come forward with information."

Mr Veale described the investigation as "complex and multi-stranded" but added: "This is not a 'fishing trip' or 'witch-hunt' - both of these terms have been unfairly levelled at us.

"The legal role of the police service is to, on behalf of the public, impartially investigate allegations without fear or favour, and go where the evidence takes us.

"I take my responsibilities of operational independence, which is the bedrock of British policing, very seriously indeed.

"Therefore I will remain operationally independent and will not be influenced by inappropriate and unacceptable pressure from people who don't know the detail of this case.

"I will not be buckling under pressure to not investigate or to conclude the investigation prematurely."

Mr Veale said investigators had not spoken to the man known as Nick who features in Operation Midland - the Met Police probe into an alleged Westminster paedophile ring.

Last weekend The Mail On Sunday reported the contents of a leaked confidential report into Operation Conifer, which referred to satanic ritual sex abuse.

"Let me be clear, this part of the investigation is only one small element of the overall inquiry and does not relate to Sir Edward Heath," Mr Veale said.

"It is also very important for me to reiterate that the report forms part of a live ongoing criminal investigation, so the disclosure of this information is something which we take very seriously."

Earlier this month two people were arrested and bailed by detectives working on Operation Conifer.

The Independent Police Complaints Commission launched a probe into alleged historical corruption after information from a retired officer raised concerns that Wiltshire Police deliberately caused a criminal prosecution to fail 22 years ago.

Earlier this year the probe found no evidence that a prosecution against a brothel keeper was dropped because of threats to allege publicly that Sir Edward had been involved in sexual offences.

Wiltshire's police and crime commissioner Angus Macpherson said: "The chief constable and I both take very seriously the duty to investigate fully and fairly all allegations or complaints that are received by the force.

"I also take seriously the need to preserve the good name of individuals, living or dead, if there is no evidential basis to allegations or complaints made against them.

"As commissioner, I recognise that the chief constable has complete operational independence in relation to the investigation of criminality. He knows he has my backing to investigate without fear or favour.

"I recognise there is a level of public interest that places additional pressure on the investigation.

"I believe the root cause of this pressure is a legitimate concern that the reputation of a former prime minister may be tarnished without there being credible evidence of guilt.

"The chief constable and I are of one mind: the police cannot act as judge and jury in their own cause.

"Once the police have conducted the investigation to a conclusion, there must be an alternative avenue to assess the credibility of any evidence that has been gathered."