The occupation of Crete by the Saracens in 824 A.D shattered the island and had serious consequences on the social, economic and religious sectors. It was a "dark" period for Kydonia.  The Arabic period lasted from 824 A.D to 961 A.D, when Crete was liberated by the forces of Nikofors Fokas. 
The historical sources from this period are few, and archeological excavations have not revealed much from this period. However, the Arabic coins found in specific regions of Crete led specialists to the conclusion that the Arabs did not conquer the entire island.
This is probably because they were pirates and only needed to occupy some coastal areas. Handax (today the city of Heraklion) was the central establishment of the pirates, and the place where they stored their treasures. During the Arab period, Crete was detached from the Byzantine Empire and suffered the darkness of a year-long Arabic night.