He has gone to the Gaza Strip to talk with the militants of Hamas and Islamic Jihad about a cease-fire ; he has warned his security chiefs to get serious about stopping violence against Israel and Israeli civilians ; he has told them to guard more strictly the crossing points in Gaza , which the militants have attacked ; and he has ordered hundreds of Palestinian security forces to deploy in northern Gaza to try to prevent the radicals from launching mortars and Qassam rockets toward Israeli settlements and towns .