The Israel Police refused to comment Thursday on reports which claimed National Fraud Unit detectives were investigating whether Prime Minister Ehud Olmert double-billed the March of the Living charity, which organizes tours of Nazi concentration camps in Poland for students. Olmert is under suspicion of asking several organizations to pay for the same flights abroad - including Yad Vashem, the Simon Wiesenthal Center, the Soldiers Welfare Association and the Ministry of Industry, Trade and Labor - and using the excess to fund personal family travel arrangements through the Rishon Tours travel agency. "I don't know anything about this," a March of the Living director said about the Channel 1 news report which aired Wednesday night. The charity was formerly headed by ex-finance minister Avraham Hirchson, who faced suspicions of stealing funds from the organization, though the allegations never reached trial. Last week, police announced a widening of the Talansky investigation, after saying evidence was uncovered showing that Olmert double-billed a number of organizations and transferred the excess to a "special private account in Olmert's name managed by the Rishon Tours travel agency." A Rishon Tours CEO told The Jerusalem Post on Thursday that he did not wish to comment over the allegations at this stage. Police are keen to wrap up the fresh investigation and the Talansky case as soon as possible, and according to most estimates the investigations will be complete by August.