"There are about 20 syndicate members all in all; whereas there are about 120,000 members in the police service," the spokesman said. "We will therefore not be intimidated by them."

Avishar allegedly had contacts with a reputed mob leader in Israel, Yossi Harari.

Avishar and his former wife, Johannesburg socialite Hazel Crane, were friends of Winnie Madikizela-Mandela, who has remained a prominent and influential politician since her divorce from former President Nelson Mandela a few years ago.

Crane is reported to have fled the country because she believed her life was in danger from members of the syndicate. Before fleeing, she reported receiving death threats from the group.

Police suspect that Avishar was murdered by another member of the syndicate after an apparent double-cross in a diamond deal.

Police have linked an additional two murders to the syndicate, and they suspect a third. In the two incidents linked to the group, the victims' heads had been covered with a shawl.

Motti Raz, who came to South Africa in 1996, apparently launched the so-called "Israeli mafia." He was later killed and his body found, also in a shallow grave, near Johannesburg.

The syndicate has been implicated in various crimes, including illegal diamond dealing, drug trafficking, protection payments and illegal firearms. It is said to operate primarily in the three largest cities in South Africa — Johannesburg, Cape Town and Durban — where Jews have been the prime targets of the group.

The police say that four syndicate members have been killed so far, all by their own people.

"They are powerful, but they are killing their own people because they are too greedy," the police spokesman said.

One suspected member has appeared in court on charges of illegal possession of firearms and ammunitio Two others are murder suspects and are on the run.