The Italian coastguard is searching for a ship carrying as many as 180 people which sent a distress signal from off the southern coast.
The ship, called the Davis, sent an SOS message last night which was picked up by Greek radio operators and transferred to Italy.
They estimated the boat to be between 24 and 30 nautical miles off the coast of Brindisi, on Italy's southeastern heel.
But the Brindisi coastguard, which searched through the night with speedboats and a helicopter, said the vessel was not in the location given.
"We're still looking. We have not identified where it is," a spokesman for the Brindisi coastguard said.
Several commercial ships in the busy Otranto channel were helping with the search.
The coastguard said it was not known precisely how many people were on board, but the ship was thought to be carrying illegal immigrants. Italian radio said the vessel was carrying at least 180 people.
Hundreds of boats ply the Adriatic, many of them bringing illegal immigrants to Italy's shores via Greece, Turkey and the Croatian and Albanian coasts.
Reuters