Interior Minister Aryeh Deri was questioned for over six hours in his fourth round of police interrogation on Tuesday, as part of an ongoing corruption investigation into a range of suspicions against him.

The minister’s wife, Yaffa Deri, was questioned separately for two hours over suspicions of various financial crimes, including tax evasion and using money donated to her nonprofit organization to purchase real estate. She has joined her husband for two of the previous three rounds of questioning.

Deri, the head of the ultra-Orthodox Shas party, was questioned on suspicion of money laundering, fraud and breach of trust, theft by an authorized person, fraudulent registration, and tax offenses, according to police.

The investigation is a joint effort of the Israel Police, Tel Aviv Income Tax Investigation Division of the Tax Authority, and the Justice Ministry’s Money Laundering and Terror Financing Prohibition Authority, under the supervision of the attorney general.

Both Deris are being questioned under caution as criminal suspects.

Writing on Twitter before arriving at the Lahav 433 anti-corruption unit in the central city of Lod, Deri said that he and his wife would “give answers to all the questions” during the interrogation.

“We have no doubt that everything will be OK and will end well, with God’s help,” Deri wrote.

Interior Minister Aryeh Deri (l) and his wife Yaffa seen leaving their home in Jerusalem, on May 29, 2017. (Yonatan Sindel/Flash90)

Interior Minister Aryeh Deri (l) and his wife Yaffa seen leaving their home in Jerusalem, on May 29, 2017. (Yonatan Sindel/Flash90)

Speaking at an informal meet-the-public legal event in June, State Prosecutor Shai Nitzan promised the police probe “will be seen through until the end.”

Deri, who served a prison sentence for graft offenses that he committed during his previous tenure as interior minister in the 1990s, has sought to downplay the allegations and said he would cooperate fully with the investigation to prove his innocence.

Israeli-Georgian tycoon and philanthropist Mikhael Mirilashvili. (YouTube screenshot)

Israeli-Georgian tycoon and philanthropist Mikhael Mirilashvili. (YouTube screenshot)

In addition to questioning the Deris, police have detained 14 people in connection with the graft probe. Among those arrested were Israeli-Georgian businessman and philanthropist Mikhael Mirilashvili along with several senior officials from the Ministry for the Development of the Negev and the Galilee, also headed by Deri.

The investigation into Deri, which police began in April 2016 together with the Tax Authority, initially focused on unreported real estate property owned by Deri and members of his family, including a vacation home in northern Israel and apartments owned by each of his nine children.

At the center of the probe is Mifalot Simcha, a nonprofit organization run by Yaffa Deri for the past 18 years. Mifalot Simcha operates educational institutions for female students and according to reports, also employs three of the couple’s daughters.

Aryeh Deri's family's vacation home in Safsufa (Screen capture: YouTube)

Aryeh Deri’s family’s vacation home in Safsufa (Screen capture: YouTube)

When he was appointed interior minister, Deri’s declaration of capital included property whose value was estimated at NIS 5 million ($1.32 million). That included his apartment in Har Nof, Jerusalem, valued at NIS 4.7 million ($1.24 million), NIS 10,000 in savings ($2,645), a stock portfolio worth NIS 300,000 ($79,350) and a NIS 60,000 ($15,870) car registered in the name of his wife.

Reports say Deri had made some NIS 2 million ($530,000) from consultancy following his release from jail.

Deri served 22 months in prison from 2000 to 2002, after he was convicted of taking bribes while serving as interior minister.

He reclaimed the leadership of his Shas party shortly before 2015’s Knesset elections, replacing Eli Yishai. He returned to his Interior Ministry post earlier this year after a court ruled his prior conviction did not disqualify him from the position.

Channel 1 news reported Tuesday that police have compelling evidence of a money laundering offense having been committed. However, the report said, the evidence against the businessmen under investigation in connection with the case against Deri is weak.

Times of Israel staff contributed to this report.