The authorities in Italy have arrested a ship's captain and a German aid official after 37 African asylum seekers were allowed to land in Sicily.
The migrants remained at sea for weeks
Elias Bierdel of the Cap Anamur group and captain Stefan Schmidt were accused of aiding and abetting illegal immigration, Italian officials said.
The German aid group said the Africans were rescued from a leaking dinghy in the Mediterranean Sea late last month.
They were allowed to disembark on Monday after being stranded for weeks.
The BBC's David Willey in Rome says their plight has touched the Italian public.
Citing strict new EU immigration laws, both Italy and Germany had previously refused to accept the asylum seekers and tried to shift responsibility to Malta, where the German-registered Cap Anamur ship made a brief call to land some other migrants.
'In decent state'
Italian police impounded the vessel and detained captain Stefan Schmidt and Mr Bierdel as part of an investigation into illegal immigration.
"We haven't yet had time to discuss this to know how we are going to react," Cap Anamur's spokeswoman Michaela Schunko was quoted as saying by the AFP news agency.
Earlier on Monday, the Africans were finally allowed to disembark and were taken to a refugee shelter at Agrigento.
"They left the boat this morning," an Italian interior ministry representative told BBC News Online.
"From what we can gather, they are in a decent state," he said.
The Italian interior ministry said the ship's captain radioed for help on Sunday morning, signalling "he was no longer able to guarantee the control of the ship and the command of the crew" and was concerned about the well-being of the migrants.
Both the United Nations refugee agency and the Vatican, who had urged Italy to let the African migrants disembark on humanitarian grounds, welcomed the decision.
"We are pleased that the Italian government decided to allow the refugees to land," Laura Boldrini, spokesperson for the UN agency, told reporters.
The migrants will now have the opportunity to apply for political asylum in either Germany or Italy, she said.
The semi-official Vatican newspaper, L'Osservatore Romano, said Italy's decision to let the Africans land was a triumph of humanity over bureaucracy.
But Germany said the refugees could not claim asylum in Germany.
"An asylum application in Germany requires one to have reached German territory," an interior ministry spokesman said.
The asylum-seekers had claimed to be fleeing the conflict in Sudan's Darfur region but the Italian authorities now say they appear to be from Ghana and Nigeria.
Italy's long and porous coastline mean it is often a target for immigrants seeking an entry-point into Europe.
The Cap Anamur organisation says it is dedicated to helping refugees in distress at sea.
The group has rescued tens of thousands of refugees at sea since it began helping Vietnam's boat people two decades ago.