عبد الرحمن الأوسط
The Andalusians also occupied several of the Cyclades during these early years, but Michael II organized another large-scale expedition, recruiting an entire new marine corps, the "Tessarakontarioi", and building new ships. Under the admiral Ooryphas, this fleet managed to evict the Arabs from the Aegean islands but failed to retake Crete. Michael II's successor Theophilos () sent an embassy to Abd ar-Rahman II of Córdoba proposing a joint action against the Andalusian exiles, but beyond Abd ar-Rahman giving his assent to any Byzantine action against Crete, this came to nothing. In October 829, those Arabs destroyed an imperial fleet off Thasos, undoing much of the work of Ooryphas and opening the Aegean and its coasts to pillage. Later they attacked Euboea (), Lesbos (837), and the coasts of the Thracesian Theme, where they destroyed the monastic centre of Mount Latros. They were heavily defeated, however, by the local "strategos", Constantine Kontomytes.