Italian authorities have arrested two survivors of Sunday's migrant boat disaster on suspicion of people trafficking, Infrastructure Minister Graziano Delrio said, after the men arrived in the Sicilian port of Catania.
Italian police interviewed 27 survivors of the wreck as they were brought to Italy on a coastguard vessel on Tuesday. As many as 800 people are believed to have drowned.
Delrio said Catania state prosecutor Giovanni Salvi, who has opened a homicide investigation into the disaster, ordered the arrest of the two. Officials from the prosecutor's office said they were the captain of the vessel and his first mate, the Reuters news agency reported.
"Prosecutor Salvi has made two arrests this evening of persons involved, which shows the Italian justice is working," Delrio told reporters at the port.
Decrying what he called an "escalation in these death voyages", Italian Prime Minister Matteo Renzi on Monday urged Europe to put the focus on preventing more boats from leaving Libya, the source of 90 percent of migrant traffic to Italy.
"We are facing an organised criminal activity that is making lots of money, but above all ruining many lives," Renzi said at a joint news conference with Malta's prime minister, Joseph Muscat. He compared their activity to that of slave traders of centuries past, "unscrupulous men who traded human lives".
The arrests came as the European Union proposed doubling the size of its Mediterranean search and rescue operations.
A 10-point plan presented by the European Commission on Monday is expected to be discussed at an extraordinary summit of EU leaders on Thursday.
1. Increase financial resources
2. Capture and destroy vessels used by smugglers
3. Gather information on smugglers and trace their funds
4. Help Greece and Italy in processing asylum applications
5. Ensure fingerprinting of all migrants in member states
6. Consider options for an emergency relocation mechanism
7. Offer a number of places to persons in need of protection
8. Establish a new programme for the rapid return of irregular migrants
9. Engage with countries surrounding Libya initiatives
10. Gather intelligence on migratory flows
"The situation in the Mediterranean is dramatic. It cannot continue like this," said Donald Tusk, the president of the European Council.
Federica Mogherini, the chief of EU foreign affairs, said the deaths of hundreds of migrants over the weekend and Monday has "finally" given the idea of "a new sense of urgency, a new sense of political will" to tackle the crisis.
Even if the move is approved, it would leave the operation smaller and less well-funded than an Italian mission that was abandoned last year due to costs and domestic opposition citing sea rescues as attracting more migrants.
Italy and Malta were working to rescue two migrant boats off the coast of Libya on Monday, with about 400 people on board.
At least 20 migrants were feared dead on the boats, the International Organisation of Migration (IOM) said after receiving a distress call from a person on board one of the vessels.
Earlier on Monday, at least 90 people were rescued after a boat carrying migrants ran aground off the Greek island of Rhodes, police said. Three deaths were confirmed by Greek coastguards.
Up to 1,500 migrants are now feared to have drowned this year alone.
'Europe must do more'
Many European governments have long been reluctant to fund rescue operations for fear of encouraging more people to make the crossing in search of a better life in Europe, but they now face increasing outrage over the latest deaths.
"Europe can do more and Europe must do more," said Martin Schulz, president of the European Parliament.
"It is a shame and a confession of failure how many countries run away from responsibility and how little money we provide for rescue missions."
William Lacy Swing, chief of the IOM, urged European countries to support Italy's Mare Nostrum rescue operation, which was stopped last year due to high operating costs.
Mare Nostrum, created after more than 350 people drowned off Lampedusa in October 2013, rescued 130,000 people last year.
Italy scaled back the operation after failing to persuade its European partners to help meet its operating costs of $12m a month.
Source: Al Jazeera and agencies