Original sentence: During the early stages of the investigations, some members of the Israeli police said that Sicarii might not be a terrorist group at all, but rather that their actions were the work of isolated extremists.Immediately after the 1989 Jaffa gate shooting, Chief Superintendent of the national police force Adi Gonen said that "there still is no concrete evidence that the Sicarii really exist", and he refused to rule out that the shooting was a criminal rather than a political act.In May 1989, the General Security Services arrested 8 Kach party activists over the Sicarii attacks, interrogated them for an hour, and then released them on bail.In early January 1990, Sicarii claimed responsibility for planting a dummy grenade under the car of the wife of Israeli Prime Minister Simon Peres.One of their members claimed that the arson attacks were not meant to kill, but to intimidate, meaning that some of their attacks may have been designed to fail.The Israeli Police started an investigation on the Sicarii attacks in march 1989, after Israeli president Chaim Herzog urged them to eradicate the Sicarii, after a caller stated that the group claimed responsibility for setting fire to the door of Petah Tikva mayor Dov Tavori.The Israeli police claimed that the group was a "clumsy, loose knit but dangerous band of amateur terrorists".They said they felt this way because of the poor execution of all the group's attacks, in contrast with the professionalism of the devices laid by Ultra-orthodox terrorists in the same period
Edited sentence: In early January 1990, Sicarii claimed responsibility for planting a dummy grenade under the car of the wife of then-Knesset member Amir Peretz