Correction: A previous version of this article stated that Maso Notarianni had been on board the Mare Jonio during the rescue operation, when he had been on board the Alex.

Rome, Italy – The Italian rescue ship Mare Jonio was 64km off the Libyan coast on Thursday evening when its crew sighted a raft in distress. The five-metre rubber dinghy was crammed with 30 people, and its engine was broken.

“It was so small that [navy] radar probably could not detect it,” said Maso Notarianni, a rescuer on board the Mare Jonio’s sister ship, Alex. “The first thing those on board told us was: ‘We come from hell’.”

The Mare Jonio, operated by the Italian charity Mediterranea, immediately alerted the Italian Maritime Rescue Coordination Centre, but were told to contact the Libyan coastguard instead.

But returning the refugees and migrants “back to a country at war, where human rights are not respected, was simply inconceivable”, said Notarianni.

The Mare Jonio headed for Italy, reaching the island of Lampedusa on Friday morning. Among those it rescued were two pregnant women and five children, including a one-year-old infant.

As the ship neared Lampedusa, two Italian maritime police boats came up alongside it. The police jumped onboard, carried out routine inspections and escorted the boat into the island’s harbour.

As the refugees and migrants disembarked, Matteo Salvini, Italy’s interior minister, tweeted: “This is their last voyage … Blocked and seized. Bye bye.” The ANSA news agency meanwhile said the Mare Jonio’s crew was being investigated for “promoting illegal migration”.

The Mare Jonio remains docked in Lampedusa, but Mediterranea said it has not received a formal notification regarding the vessel’s confiscation or the launching of a criminal investigation.

“We are not promoting any illegal immigration. We are simply saving asylum seekers in the middle of the sea,” said Notarianni.

‘Temporary seizure’

The Italian-flagged Mare Jonio was briefly impounded last month, too, when it docked in Lampedusa with 49 refugees and migrants it rescued off the coast of Libya. Notarianni dismissed the new threat from Salvini saying: “A formal investigation could imply a temporary seizure, but it’s just a standard procedure.”

Salvini, who has accused rescue groups of being “accomplices to human traffickers”, refuses to let refugee rescue ships dock in Italy, the main entry point for many of those making the perilous Mediterranean Sea crossing from northern Africa to Europe.

Since taking office last June, he has been at the centre of several international standoffs over the docking of rescue ships, only backing off when other European Union member states to take in those rescued at sea.

Last month, his ministry issued a directive barring ships that are not Italian and do not coordinate with authorities in Rome from using its ports.

While Salvini’s hardline position has seen a stark drop in new refugee and migrant arrivals to Italy, it has also caused an increase in deaths at sea, according to rights groups.

Meanwhile, boats that do pick up refugees in distress are increasingly returning them to war-torn Libya, where the United Nations says they face trafficking, kidnap, torture and rape.

On Friday, at least 65 people drowned off the coast of Tunisia when their boat sank, according to the UN.

“If we want to avoid such tragedies, we need to coordinate all the rescue operations, stop criminalising NGO vessels and open a humanitarian corridor from Libya,” Luca Maria Negro, president of the Italian Federation of Evangelical Churches, said in a statement.

Mediterranea said its rescue operation was lawful and was not afraid to prove it.

Judith Sunderland, associate Europe director of Human Rights Watch, agreed.

“Over the past year, there have been many investigations – efforts by the government of Italy, and those of other countries including Spain and Malta to prosecute NGO workers,” she said. But “no evidence of wrongdoing” has been found by rescue organisations.