Detectives from Manchester are in contact with officials in southern Europe over the possible exhumation of a former patient of Dr Harold Shipman.
Yesterday, murder squad officers continued to question the 52-year-old general practitioner from Greater Manchester in connection with further deaths. The bodies of four of his former patients have already been exhumed.
Dr Shipman, of Mottram, Tameside, is remanded in custody, charged with the murder of Kathleen Grundy, a widow aged 81.
He is also charged with falsely obtaining cash and property worth pounds 300,000 and forging a will and two letters.
The body of Mrs Grundy, a charity worker and former Mayoress of Hyde, was exhumed on 1 August. A coroner gave permission for her grave to be opened a month after she was buried alongside her parents. The inquiry began when Mrs Grundy's daughter, Angela Woodruff, who lives in the Midlands, contacted the police after relatives expressed concernsover her death.
Police have said that the records of 28 of the GP's patients at his surgery at Market Street, Hyde, are being looked at as part of the investigation. More than 20 of those under scrutiny were cremated.
Last month, the remains of Winifred Mellor and Joan Melia, widows aged 73, and Bianka Pomfret, 49, were exhumed from cemeteries. The death certificate for Mrs Pomfret, who died last December, was signed by Dr Shipman. He cited the cause of death as coronary thrombosis linked to heart disease from smoking.
Greater Manchester Police said: "We can confirm that Dr Harold Shipman is being interviewed in connection with further offences."
Police declined to comment further on the widening of the inquiry, but it is understood that three more bodies may be exhumed. Detectives have travelled to the Mediterranean to discuss procedures for a possible exhumation with a local coroner. This latest line of inquiry was prompted by relatives of another of Dr Shipman's female patients who died in Hyde but was buried near her birthplace in south-east Europe.
Dr Shipman has been in practice in the town for more than 20 years.
Although detectives have declined to give further details, it is believed they are studying many more cases in response to approaches from worried relatives. Detectives working from a special incident room at Ashton-under- Lyne in Greater Manchester are expected to be working for another 12 months on the extensive inquiry.
The GP is on remand in Preston jail after being moved from Strangeways Prison, Manchester, for his own safety. He is due to be committed for trial on 10 November.
He is awaiting the outcome of an NHS tribunal that convened last week to consider a request by West Pennine health authority to suspend him.