A Turkish-flagged ship carrying hundreds of illegal immigrants that floated outside Greek waters for five days under close observation by the coast guard and navy left for an unknown destination yesterday. The Rafet Captan freighter, believed to be carrying some 400 illegal Asian immigrants, was sailing off the southern Peloponnese early yesterday, according to coast guard sources. It then made off toward Italy or Libya. The vessel appeared off the Dodecanese islands of Tilos and Halki on Wednesday, and was immediately placed under surveillance by coast guard and navy vessels that intercepted its captain’s attempts to enter Greek waters. Since Friday, Greek authorities have arrested 29 illegal immigrants in the eastern Aegean. Over 4,000 have been arrested this year.