Among those arrested is Nir Hefetz, Netanyahu's former family spokesperson, and Shaul Elovitch, the multi-millionaire owner of an Israeli news organization who is considered a close friend of Netanyahu.
Earlier in the day, a court remanded Hefetz in custody until Thursday.
The news station reported Tuesday that his testimony would mark a turning point in the investigation, and could lead to further dramatic developments.
The allegations center on an investigation into Netanyahu's wife, Sara, who is suspected of misusing funds at the couple's official residence. A statement issued on Sunday by a personal spokesman to Netanyahu said all decisions related to Bezeq "were made according to recommendations of expert committees and expert officials". "Therefore the claim that I acted for the benefit of Bezeq at the expense of professional considerations is simply and fundamentally baseless".
Police, he said, "are creating new cases every two hours".
Nir Hefetz, also a former spokesman of Netanyahu, is suspected of offering a retired judge, Hila Gerstel, the position of the attorney general if she would drop a corruption case against Netanyahu's wife Sara.
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Netanyahu is not now suspected of dispatching Hefetz to extend the offer to the judge, Hadashot TV reported. "I can not believe he raised this possibility with anyone", Netanyahu said.
Israeli Prime Minister Benjamin Netanyahu leaves the Muni World conference in Tel Aviv on February 14, 2018.br / Netanyahu said today his government was "stable" and criticised the police investigation against him after detectives recommended his indictment for corruption, prompting calls for him to resign.
The revelations come just days after police said there were grounds to indict the prime minister himself in a separate case for bribery, fraud and breach of public trust, in the biggest challenge yet to the right-wing premier's long tenure in power. Police have not named him as a suspect but have questioned his close associates on the matter.
In Case 1000, Netanyahu and his wife are alleged to have received illicit gifts from billionaire benefactors, most notably the Israeli-born Hollywood producer Arnon Milchan, totaling NIS 1 million ($282,000).
Netanyahu denies any wrongdoing and says the latest charges against him were merely a continuation of a wider media orchestrated witch hunt against him and his family.
In the second case, Netanyahu is accused of offering a newspaper publisher legislation that would weaken his paper's main rival in return for more favorable coverage.
Hefetz, who served as the prime minister's media adviser from 2014 to 2017, is under arrest for his alleged involvement in that case.