Hamas has vowed to step up suicide attacks in response to two Israeli Defense Forces attacks in Gaza Feb. 11 that killed 15 Palestinians. Israeli police are on high alert, and visitors should follow security guidelines posted by the U.S. Embassy in Tel Aviv and the Consulate General in Jerusalem. This advice includes avoiding discos and clubs, all large crowds or gatherings, and restaurants, cafes, malls or theaters, especially during peak business hours. The guidelines also recommend avoiding JerusalemÂ’s Old City after dark and Friday between the hours of 11 a.m. and 2 p.m., and the downtown areas of West Jerusalem and City Center. The Ben Yehuda Pedestrian Mall, Mahane Yehuda Market area of West Jerusalem, King George Street between Ben Yehuda and Jaffa Street, and Jaffa Street are also off-limits to Embassy personnel.