Two inspectors and three sergeants "failed to be conscientious and diligent" in their handling of a detained man who later died, a police watchdog said yesterday.

Nicholas Wootton was not given a medical examination despite telling officers from Dyfed-Powys Police he had a heart condition following his arrest on suspicion of drink-driving.

The 56-year-old from Llanfair Caereinion near Welshpool, Mid Wales, was released from custody after spending the night in cells at Newtown Police station but died just hours later after a taxi ride home. An inquest in Welshpool has determined today that he died of natural causes.

The IPCC sent a file to the Crown Prosecution Service who advised that there was insufficient evidence to prosecute any officers.

In addition to the post-mortem, the IPCC also sought a toxicology report and expert advice from a clinical pharmacologist and a consultant cardiologist as part of their inquiry.

Tom Davies, the IPCC Commissioner for Wales, said: "The inquest must have been a very difficult time for Mr Wootton's family and friends and my condolences go to them.

"The IPCC investigation has made two recommendations which Dyfed-Powys Police have accepted. These both relate to the obligations the Police and Criminal Evidence Act (PACE) place on custody staff when dealing with prisoners who have heart conditions.

"Dyfed-Powys Police have confirmed to the IPCC that they are reminding custody staff of their obligations.

"When Mr Wootton was taken into custody he told officers that he had a heart condition and for which he was taking medication. This should have triggered the custody staff into seeking a medical examination.