Rome, May 26 - Some "20-30" people were said to have drowned in the latest in a string of migrant boat disasters off Libya Thursday. The boat was said to be carrying about 100 people. About 50 have been saved, according to sources at the EU mission EUNAVFOR MED. The disaster followed another one in the same area of the Sicilian Channel Wednesday in which five people died and some 560 were rescued. A Luxembourg helicopter taking part in Operation Sophia spotted the capsized vessel about 35 nautical miles off Zuara. An alert was sent out and a second EUNAVFOR MED helicopter arrived to throw life-jackets into the water. Two motorboats from the Italian Coastguard are also in the area along with a Spanish ship from the EU mission, Reina Sofia, which is rescuing the migrants.