The names of the six suspects arrested Monday as part of a probe into suspected diamond smuggling in which Israeli tycoon Lev Leviev is implicated were made public on Tuesday. One of the suspects is Leviev's son and another is his relative.

The three others detained are former and current employees, including Hananya Issachar, Reuven Shmuelov and Asher Yechieli, who was the former manager of Leviev's plant in Russia. Yehuda Asor, the sixth suspect, is accused of serving as a courier and smuggling diamonds into Israel.

>> Israeli diamond industry at a loss to explain Leviev smuggling allegations

Leviev's companies allegedly are at the center of a vast diamond-smuggling ring that has operated for years.

Police want to question Leviev as well. A source close to the Uzbekistan-born Leviev said he might return to Israel voluntarily for questioning.

On Tuesday, the Tax Authority and the Israel Police seized assets worth tens of millions of shekels owned by Leviev.

Among the assets seized, a warning was listed in the land registry regarding Leviev's private villa in the town of Savyon. Other assets seized include property of Leviev's company LLD, including cash and diamonds found at the company's offices on Monday.

“This is an investigation that began at the end of March 2018,” a police spokesman said, putting a value on the suspected offenses of $81 million (300 million shekels). “The criminal offenses are attributed to all the suspects in the operation, in the framework of their work with [Leviev diamond company] LLD, with the exception of one suspect.”

Amit Hadad, the lawyer for one of the Leviev relatives, said his client did not work for LLD.

“True, he owns 1 percent of the shares, he was chief executive and was replaced in 2011 by Zvulun Leviev,” the police spokesman said, adding that there was a dispute in the Leviev family.

LLD responded in a statement: “Mr. [Lev] Leviev and the companies under his control are acting in accordance with the proper norms, while adhering to the law, and we hope that the matter will soon be clarified and the suspicions proved baseless.”

The arrests followed the arrest of a so-called mule at Ben-Gurion International Airport months ago. That triggered a joint police and customs investigation; the state suspects that for years people working for Leviev took part in a diamond-smuggling operation.