Men held in Sicily accused of intercepting vessels and demanding cash, phones and vital engines.
Police in Italy have arrested four Tunisians on charges of piracy, accusing them of intercepting migrant boats in the central Mediterranean and stealing their engines, leaving the vessels adrift.
Investigators said the four men would identify boats carrying asylum seekers to Europe and, with the help of other vessels, blockade them in international waters off the Tunisian coast, before boarding them to rob the passengers of money and phones and the boat of its valuable engine.
One migrant described an attack: “They cut us off course, as if they wanted to ram us. Then they boarded us. They were armed with knives and threatened us that if we didn’t give them the engine they would hurt us. We had no choice.”
Salvatore Vella, the head prosecutor in Agrigento, Sicily, said authorities had become increasingly aware of apparent engine thefts. “We had noticed that half of the small iron boats recently used by migrants departing from Tunisia to reach Europe, and which were rescued by the Italian coastguard, were without engines.
“This evidence matched what witnesses among the asylum seekers had told us, that they were attacked by Tunisian men who robbed them and stole their engine.
We gathered as much information as possible, and we intervened at sea, arresting the men who operated on a fishing boat.”
Police found at least three allegedly stolen engines on the boat, hundreds of euros and dozens of mobile phones. Italian police were able to carry out the arrests in international waters due to the Montego Bay convention, which allows all states to intervene in the suppression of piracy on the high seas, or in any other place beyond the jurisdiction of any state.
The Tunisians, who were arrested on 24 July, are being held in a prison in Sicily. Investigators are trying to determine whether they were operating on their own or acting on behalf of human traffickers.
“Why did they steal these engines?” said Vella. “It is possible that they then tried to resell them. But we cannot exclude that these men could also work for human traffickers in the Sfax region of Tunisia, from where most asylum seekers depart to reach Europe.
“At the end, the engine of these boats is the most valuable part in these boats. Is it possible that these pirates stole the engines to be able to reuse them on other migrant boats? Yes, it is possible.”
Migrants are trying to cross the Mediterranean sea in precarious metal boats, which makes the voyage even more dangerous. More than 20,000 deaths have been recorded on this route since 2014, according to the UN.
The vessels are produced cheaply and soldered together. Asylum seekers say they begin to take on water as soon as they reach the open sea. If also deprived of its engine, the consequences for a boat’s passengers are deadly.
Tunisia has surpassed Libya as the principal departure hub for migrants. The sea route to Italy is the world’s most lethal and described by NGOs as a “liquid graveyard’’.
Several witnesses among migrants reported that Tunisian coastguards have removed their vessel’s engine, beaten and abandoned them at sea, in order to stop them from leaving.
On 16 July, the EU signed off on a €1bn (£860m) deal with Tunisia to help stem irregular migration. Recently, the country has been accused of removing hundreds of sub-Saharan African migrants to a desolate area along the border with Libya.
Libyan border guards and aid workers said they had rescued dozens of migrants they said had been left in the desert by Tunisian authorities without water, food or shelter, with many left to die in the extreme heat.