Police officials sent a shiver of fear through the legislature Tuesday when they announced that a senior Knesset official may have been the target of an assassination attempt two months ago. Prof. David Niv, director of the pain clinic at Tel Aviv's Sourasky Medical Center, was shot to death on February 6 while driving home on the Aluf Sadeh Highway in Ramat Gan. His car was riddled with bullets and investigators said it looked like the work of professional hit men. Last week, Fatah's Aksa Martyrs Brigades posted information on their Web site taking responsible for the attack, but saying they had mistakenly killed Niv while targeting an MK. That claim led a Knesset security officer to send a letter to all 120 lawmakers Tuesday, asking that anybody with a silver BMW and license plates matching certain numbers report to the Knesset Security Office. Several legislators, including MK Avigdor Yitzhaki and Deputy Knesset Speaker Majallie Whbee, both of Kadima, reported to the security office. It was soon discovered that Yitzhaki's car did not have the correct license number, and that Whbee's car, which is usually driven by his son, is gold rather than silver. In the end, Knesset security officers reported that neither MK's vehicle was a close fit for the car and license plate number they were searching for, and that it was likely that the Aksa Martyrs Brigades' claim was "nothing more than an attempt to spread fear." Security officials have received intelligence warnings on plans to assassinate MKs and senior officials in the past. In October 2001, tourism minister Rehavam Ze'evi was killed by the Popular Front for the Liberation of Palestine while entering his hotel room in Jerusalem.