Police are investigating criminal allegations against coalition chairman and Likud party Knesset member David Bitan, Haaretz has learned.

In the past few months, detectives from the Israel Police national fraud investigation unit have taken witness statements and reviewed evidence.The investigation was approved in advance by Attorney General Avichai Mendelblit and State Prosecutor Shai Nitzan.

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Police have also interviewed senior municipal officials in Rishon Letzion. Bitan was a deputy mayor of the Tel Aviv suburb before he was elected to the Knesset in the March 2015 general election. The probe focuses on Bitan’s dealings with a number of businessmen.

Responding to the news, Bitan denied wrongdoing and said the timing of the report was suspicious and part of an attempt to "weaken" him. "The shameful witch hunt conducted by Haaretz against right wingers and anyone who does not agree with their agenda has broken new records this morning. The gap between the questions posed to me and the regurgitated story published this morning speaks wonders. For some time now the paper has been recycling stories about cases examined by the police and closed.

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Before he became an MK, Bitan was a strong presence in Rishon Letzion. He was elected to the city council in 1988 and appointed deputy mayor in 2005. From 2008 to 2010, and then again from 2013, he chaired the local zoning board and held the city’s engineering portfolio.

During this period, Bitan also went into debt and took out loans in the “gray market.” His wages were garnished and the Bailiff’s Office launched debt collection proceedings against him.

Individuals who were in contact with him during this period said in sworn statements that Bitan told them that he owed a total of 7 million shekels (around $2 million at current exchange rates) and was being pursued by gray-market debt collectors.

In a report in TheMarker last year, a senior city official said Bitan briefly went “underground” for fear of his creditors.

“One day, two thugs entered my office; one look and you knew what they were,” the official was quoted as saying.

“They immediately began yelling, ‘Tell us where David Bitan is.’ I said, ‘Listen to me, I’m looking for him just like you are.’”

Local papers reported on Bitan’s debts and there was speculation about how he managed to repay them.

In 2010 a criminal investigation was launched against Bitan that led him to resign from his city government positions related to building, but the investigation was eventually closed by prosecutors from the Central District.

In an interview with the Israel Channel 10 investigative program “Hamakor,” Bitan vehemently denied claims that third parties had paid some of his debts, saying he had never taken favors from anyone.

Some of the statements that were collected by police referred to checks that building contractors and other interested parties in Rishon Letzion allegedly gave Bitan to cover his loans when he was in charge of construction permits and regulatory compliance in the city government.

Bitan was elected to Knesset in 2015 as a representative of the Likud’s coastal plain district, and quickly became a dominant figure in Likud and national Israeli politics.

Prime Minister Benjamin Netanyahu appointed the freshman legislator chairman of the House Committee, and a year later he was named coalition chairman.

Bitan is considered one of Netanyahu’s closest associates, and some political observers have said that they believe he will be appointed to a cabinet position, at the very least, at the earliest opportunity.