LANDOWNERS and conservation charities are involved in a war of words over speculation about the recent deaths of birds of prey in the Highlands.

The body which represents Scottish estate owners has accused conservation groups of driving internet rumours that landowners may have poisoned around 20 raptors, including buzzards and red kites, which were found dead in Conon Bridge.

In a letter to today's Herald, Scottish Land and Estates (SLaE) say the claims have wrongly sullied the reputation of their members. It pointed to the RSPB and Scottish Wildlife Trust's public comments in the aftermath of the birds' discovery in March.

The RSPB and the Scottish Wildlife Trust called for landowners to face jail terms if illegally killed birds of prey were found on their property.

Last week, Police Scotland said the raptors, whose deaths are the latest in a series, were not deliberately targeted. Officers investigation the incident believe they were accidently killed by pest control measures.

Now the landowners' association has issued a staunch defence of its members. Tim Baynes, ­director of the Moorland Group at SLaE, claimed the conjecture surrounding the incident has fuelled negative sentiment towards landowners in Scotland.

In the letter, Mr Baynes called on the RSPB and other groups to avoid making public accusations without proof and before official investigations are completed.

Mr Baynes said: "Despite the trend of crimes against birds of prey having gone down in the last three to five years, particularly by poisoning, the speculation around each case has become more hysterical.

"The RSPB even tried to link the Conon Bridge incident to grouse-moor management.

"There are now websites and bloggers and organisations involved in police investigations who are not slow to feed ­information to the media and promote speculation.

"This speculation is having a corrosive knock-on effect on many other aspects of land management, severely straining the relationship between land managers and conservation bodies."

Mr Baynes said any deliberate killing of a bird of prey was illegal and should be condemned, but added it was not in "anyone's interests that various activists and organisations can leap to conclusions without any evidence to support their point of view, which in turn is afforded political and media credence."

He added: "It would be a major step forward if government and other interested organisations were to take a lead in ensuring that reckless speculation should be discouraged."

However, Duncan Orr-Ewing, head of species and land management at RSPB Scotland, hit back at the claims, pointing to a year-on-year increase in the number of raptors being killed.

He said: "Contrary to the assertions of Tim Baynes, the 2013 ­wildlife crime statistics show an increase in the number of reported crimes against birds of prey in comparison to 2012.

"These despicable crimes included the poisoning of a golden eagle, and the killing of red kites and hen harriers, and pre-date the Conon Bridge incident."

Jonny Hughes, chief executive of the Scottish Wildlife Trust, said:"The criminal investigation is still ongoing and it is important that all evidence is considered carefully. Raptor persecution is a serious crime which can carry a prison sentence and the Scottish Wildlife Trust would urge people to remain vigilant and report any incidents to the police."

Police inquiries into the incident are continuing.