Police didn't name the politicians involved when making the announcement on Wednesday. After a yearlong covert operation, police said they are investigating 30 suspects including a deputy minister, a former minister, mayors and others.

In a statement, police said officials are suspected of nepotism, and illegally transferring funds to various bodies.

Deputy Interior Minister, Faina Kirshenbaum, of Foreign Minister Avigdor Lieberman's Yisrael Beteinu party, confirmed that she had been called in for questioning while denying any wrongdoing.

"I am sure of my integrity and I have no clue what the investigation is about," Kirshenbaum told Channel 2 TV.

Yisrael Beteinu is an important player in Israeli elections set for March. It is not clear how the police investigation would affect the politicians involved or the elections.