Nearby merchant ships lined up to form a barrier to protect the ferry from towering waves and facilitate rescue. As darkness fell, Italian Defence Minister Roberta Pinotti said rescue operations would continue throughout the night.
Journalist Anthee Carassava told CBC News on Sunday morning that survivors reported three fires started on the vessel.
"The company still has not issued any official claim or cause for this fire," Carassava said from Athens. "The question mark is what really went wrong and what caused these three simultaneous fires in the front, in the middle and in the rear."
Carassava said the route serves thousands of tourists and is popular for people headed to mainland Europe from Greece.
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