Athens: Italian officials boarded a cargo ship carrying hundreds of migrants on Tuesday after it left Greek waters and headed towards the coast of southern Italy, the navy said.
Three coast guard officers were landed from a helicopter to assess whether the Moldovan-flagged Blue Sky M was able to navigate safely.
The vessel, which the navy estimates is carrying around 600 migrants, was spotted close to the coast of Corfu earlier in the day after authorities got an alarm call about a potential incident on board.
Greek state television said the alarm had been raised because armed men were on board, but there was no confirmation from the defence or shipping ministries.
Greek naval and coastguard vessels as well as a military helicopter were sent to the scene, but the ship was allowed to continue into international waters after the captain assured officials the situation was under control.
"He said there was no problem and he would continue on course towards Italy," said a shipping ministry official, who declined to be quoted by name.
According to figures from the United Nations refugee agency, 160,000 migrants arrived by sea in Italy and another 40,000 in Greece between January and the end of November.
Fleeing the Middle East and North Africa and often travelling in small, unsafe boats, thousands more have died attempting the journey.
The civil war in Syria and near-anarchy in Libya have worsened the crisis.
The influx has stirred some tensions among Greeks and Italians, whose own living standards have been eroded by pressure on their governments to cut spending and raise taxes since the euro zone debt crisis.