REUTERS, Tel Aviv

Israel’s arrest of almost 30 mostly Jewish citizens who allegedly spied for Iran in nine covert cells has caused alarm in the country and points to Tehran’s biggest effort in decades to infiltrate its arch foe, four Israeli security sources said.

Among the unfulfilled goals of the alleged cells was the assassination of an Israeli nuclear scientist and former military officials, while one group gathered information on military bases and air defences, security service Shin Bet has said.

Last week, the agency and Israel’s police said a father and son team had passed on details of Israeli force movements including in the Golan Heights where they lived.