Italian authorities sent two helicopters Tuesday to meet a cargo ship believed to be carrying hundreds of migrants after a passenger sent a distress call earlier when the ship was off Greece.
The operation came two days after a Greek-operated ferry caught fire between Greece and Italy with the loss of at least 11 lives, prompting a two-day search and rescue effort.
Italian air force spokesman Capt. Stefano Testa said the Moldovan-flagged Blue Sky M freighter was about 20 miles (30 kilometers) off Santa Maria di Leuca, on the southernmost tip of the "heel" of boot-shaped Italy.
Port officials in Bari said the teams were landing on the ship as a precaution to see if there were any problems on board and ensure the situation was under control.
Earlier, Greek authorities scrambled a navy frigate and helicopter after a man who said he was a passenger called emergency services when the ship was off Corfu, saying hundreds of migrants were on board and needed water, food and blankets.
A Greek coast guard official said the helicopter located the ship within Italian waters, and its captain said the vessel wasn't in distress and didn't require assistance.
Italian authorities were notified, and the cargo ship continued on its own toward Italy, the official said on condition of anonymity because he wasn't authorized to speak on the record.
Tens of thousands of migrants and refugees, most fleeing conflict or poverty in the Middle East, Africa and Asia, attempt to reach the European Union each year, most heading by sea to Italy or Greece.
On Sunday, the Norman Atlantic passenger ferry caught fire in the same area. Authorities rescued more than 400 people, and are still searching for potential missing passengers from the vessel.