JERUSALEM (JTA) — A former media advisor to Israeli Prime Minister Benjamin Netanyahu and his family has turned state’s witness in a corruption investigation, which could strengthen the case against the prime minister.

Nir Hefetz signed the state’s witness agreement on Sunday night, the Israel Police said in a statement on Monday afternoon. Hefetz was released from police detention on Sunday after two weeks in jail. He will remain under house arrest until March 13.

Hefetz is a suspect in the investigation dubbed Case 4000, or the Bezeq corruption probe, according to reports. Both Benjamin Netanyahu and his wife Sara were questioned, separately, in relation to Case 4000, each for about 5 hours on Friday.

Shlomo Filber, the suspended director general of the Ministry of Communications, last month turned state’s witness in the same investigation. Filber agreed in exchange for a lighter sentence to provide police with information about Netanyahu’s part in Case 4000, which alleges that Shaul Elovitch, majority shareholder of Bezeq, received political favors for the Israeli telecommunications giant in return for favorable coverage of Netanyahu on the Walla! news website owned by the company.

Netanyahu has denied wrongdoing in the case and others against him.

Here is why I'm matching up to $36,000 in gifts to the Forward:

Hello, fellow Forward reader! I’m Joel Brown, a Forward reader and supporter for more than 15 years, and currently the chair of the board of directors.

I’m an avid Forward reader because it ticks so many of my essential boxes: excellent journalism, Jewish focus and diverse viewpoints. In today’s political climate, what I most appreciate is the Forward’s independence — made possible by the generosity of its membership.

The Forward is committed to bringing you unbiased, nuanced Jewish news. From my position as board chair, I see an exciting future as we expand our position as the definitive independent voice of contemporary American Judaism.

That’s why I’m paying it Forward, by matching $36,000 of reader gifts. It’s an investment in the Forward’s newsroom, to continue telling the American Jewish story with truth and independence.

Don't just read the Forward - invest in it. Will you help support the Forward's work today?

— Joel Brown, Forward board chair

Support our mission to tell the Jewish story fully and fairly.

$120 $180 $360 OTHER AMOUNT