(File photo)Israeli Prime Minister Benjamin Netanyahu and his wife Sara attend an inauguration ceremony for a fortified emergency room at the Barzilai Medical Center in Ashkelon, southern Israel, February 20, 2018. (Reuters photo)

JERUSALEM, March 26 (Xinhua) -- Israel's Prime Minister Benjamin Netanyahu and his wife and son were questioned by the police on Monday over corruption investigation that also involves the country's largest telecom company.

A police spokesperson confirmed that Netanyahu was questioned at the official Prime Minister's Residence in Jerusalem. His questioning lasted about four hours.

In the same time, his wife, Sara Netanyahu, was separately questioned at the offices of Lahav 433 anti-corruption unit in Lod, outside Tel Aviv, and their son, Yair Netanyahu, was questioned at the office of the Israel Securities Authorities.

An earlier statement said that Shaul Elovitch, the control-holder of Bezeq telecom and a major suspect in the affair, was also questioned.

The Netanyahus are suspected of being involved in a bribery case, dubbed "case 4,000," in which Elovitch's Bezeq received regulatory and financial benefits from the Communication Ministry, during Netanyahu's term as the communication minister. In exchange, Netanyahu received positive coverage in Walla, a news site controlled by Elovitch.

It was Benjamin and Sara Netanyahu's second questioning in the "case 4000" and the first time Yair Netanyahu was questioned.

The questioning was the first time the suspects were confronted with information provided by Nir Hefetz, Netanyahu's former media adviser and until recently one of his closest associate, who turned a state witness against him last month.

Netanyahu and his associates have been entangled in at least four corruption investigations over the past months.

The long-time leader denies any wrongdoing and maintains that the investigations are part of a witch-hunt perpetrated by the media and "the left."