AlQa'dah 15, 1433, Oct 1, 2012, SPA -- Greek police made more than 150 arrests in the western port city of Patras on Monday as part of their recent campaign to hold and deport illegal immigrants, radio reports said, according to dpa. Officers said they raided dozens of abandoned buildings around the city's port, where the immigrants were reported to be living as they attempt to sneak onto ferries bound for Italy. Authorities said any immigrants found to be lacking residence permits would be transferred to reception centres to await deportation. A police statement said more than 29,000 people have been detained in the greater Athens area since the Xenio Zeus campaign started at the beginning of August, with 2,599 of those arrested. Greece is the main entrance point to the European Union for tens of thousands of illegal immigrants every year, mainly coming from Africa and Asia.