AL-FASHER, Aug 31, SPA -- The United Nations has put ahelicopter on standby and set up a crisis management centerin Darfur in an effort to locate eight Sudanese aid workersmissing in rebel-controlled territory, officials saidTuesday. Sudanese officials charged that the aid workers _ threefrom the U.N. World Food Program and five from the SudaneseRed Crescent _ had been kidnapped by rebels waging an 18month insurgency against the government. --SPA1314 Local Time 1014 GMT www.spa.gov.sa/196707