The Scotsman reported that police officials detained Blair's head of government relations, Ruth Turner, on Friday to question her over a series of e-mails over the past few years that linked her to the selection of candidates for the titles.
With Scotland Yard investigating Turner, many have speculated that it will only be a matter of time before the expanding investigation finds Blair himself under the microscope, the newspaper said.
To date, the investigation into the scandal has resulted in three arrests, including Merlin Biosciences founder Christopher Evans, who lent $1 million to the Labor party.
The office of the prime minister, who recently traveled to Lebanon and Israel with his fundraiser Lord Michael Abraham Levy, has offered no comments regarding Scotland Yard's investigation, said the paper.
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