A suspicious object was found on Thursday under a car in the building in which alleged crime boss Amir Mulner lives. The object did not appear to be placed under his car, police said.
Police sappers were investigating the item.
The finding comes two weeks after a car bomb exploded in Netanya, killing one and wounding another member of the rival Abergil suspected underworld organization.
The situation has become so noticeable that in February the US added a paragraph about organized crime to its Israel travel warning, saying that violent confrontation between underworld organizations has led to the death and injury of innocent bystanders.