Tests carried out in the UK on a British couple who died while on a Thomas Cook holiday in Egypt have reportedly been unable to establish the cause of their deaths.

John and Susan Cooper, died on August 21 while staying at the Steigenberger Aqua Magic hotel in the Red Sea resort of Hurghada.

The Egyptian authorities said they had died as a result of E. coli infection and inquests into the deaths are due to open at Preston coroners’ court today.

Lawyers for the couple’s daughter said that the initial examination of the couple’s bodies after they were returned to the UK last week had failed to establish a cause of death and further tests are being carried out.

Kelly Ormerod, who was on holiday with her parents and her three children, has said she does not believe they died as a result of E. coli.

Her lawyers said she believes the conduct of the Egyptian authorities has been “little short of disgraceful” and she is preparing to make a formal complaint, The Times reported.

Her solicitors, Smith Jones, said: “We can confirm that a Home Office post mortem [examination] has now been carried out on John and Susan Cooper.

“Unfortunately, notwithstanding the ‘positive’, though contradictory, assertions of the Egyptian authorities, the results of that post mortem were inconclusive, and the pathologist was unable to ascertain the likely cause of death in either case.

“It is understood that further toxicological screening and other relevant tests will now be carried out as a matter of urgency to aid that process.”

The firm added: “Kelly and her family remain committed to establishing the true cause of John and Susan’s deaths and holding those responsible to account. They look forward to assisting the coroner in whatever way they can with what they acknowledge will be a difficult and complex task.”

Ms Ormerod has said she has “no faith” in the Egyptian authorities, who said their examinations showed Mr Cooper, 69, suffered acute intestinal dysentery caused by E. coli, and Mrs Cooper, 63, a Thomas Cook travel agent, suffered a complication linked to infection, likely to have been caused by E. coli.

Egypt’s chief prosecutor, Nabil Sadek, said the bodies of the couple showed “no criminal violence” and other tests of air and water at the hotel found nothing unusual.

Lancashire coroner Dr James Adeley has said post-mortem tests began on Thursday, but “analysis and examinations of the findings… may take some weeks or possibly several months”.

Thomas Cook reported that its own tests identified a high level of E. coli at the hotel which would “explain the raised level of illness reported among guests”.

The company moved 300 guests out of the hotel 24 hours after the couple died as a precaution.

The room next door to the Coopers had been fumigated with an insecticide normally used in agricultural fields hours before their deaths.

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