Al-Quds city, April 29, SPA -- Palestinian security officials detainedfour extremists for questioning after a barrage of mortar shells and homemade rockets were fired at Jewish settlements in the Gaza Strip this week, Palestinian security officials said Friday. The four members of the Al Aqsa Martyrs' Brigades, were called in for questioning Thursday, the officials said. Al Aqsa officials said they had not heard from the mensince they were detained. Abbas and Israeli Prime Minister Ariel Sharon agreed to acease-fire in February, calling a halt to more than fouryears of violence between the two sides.--SPA1445 Local Time 1145 GMT www.spa.gov.sa/258720