Prosecutors also asked for the seized vessel to be returned to the organization. The preliminary investigations judge (GUP) adjourned the case to rule on the requests.

The crew members were originally accused of serving as a "taxi" for migrants rather than rescuing them, taking migrants on board from ships operated by Libyan traffickers and allowing the latter to turn back undisturbed after they had handed over their passengers.

Defendants express 'relief and dismay'

The interior ministry, which had joined the suit as plaintiff, said through its legal representative that it would abide by the decision of the preliminary hearings judge.

"In its statement, the prosecution admitted the lack of credibility of its main witnesses and the absence of evidence to prove that the defendants had committed a crime", said Iuventa representatives.

"The prosecution observed that the preliminary hearing offered more evidence and information than previously obtained", they added in a statement.

"Although they are relieved, defendants have expressed dismay over what they have described as the prosecution's inability. Crucial evidence, like doubts on the credibility of the state attorneys' witnesses, should have been dealt with during the phase of the investigation, not during the preliminary (judicial) proceeding," continued the statement.

Also read: Charged with saving migrants' lives – rescuers facing criminal prosecution

The case dates back to 2017, when prosecutors in Trapani investigating rescue operations carried out in the Strait of Sicily by vessels run by NGOs requested and obtained the seizure of the Iuventa on charges that crew members had allegedly aided and abetted illegal immigration.

Investigators said they had discovered at least three cases in which crew members were in contact with Libyan traffickers, claiming they had carried out rescue operations even if refugees were not in real danger.

The migrants were then allegedly taken on board the vessel operated by the NGO and escorted by the Libyans, investigators claimed.

Then-prosecutor Ambrogio Cartosio said at the time that there was "serious proof of guilt."

Also read: Italy to launch trial against sea rescue NGOs

'Groundless trial unfair', Iuventa legal team says

"We are happy that the State attorney's office has changed its mind after seven years, but it shouldn't work this way under the rule of law. The charges should be formulated only after an in-depth investigation and the collection of all available evidence," said Francesca Cancellaro, one of the lawyers representing the German NGO that owns the Iuventa vessel. "Starting a trial without the necessary groundwork is unfair and weighs unjustly on the defendants."

"The defence has stressed that it even presented a motion to shelve the case in 2019, providing all the evidence and material on which the prosecution is now basing its decision, after years. However, it looks like the prosecution didn't even examine the evidence, opting instead to start a trial despite the lack of substantial fundamentals", she explained.

Nicola Canestrini, another lawyer, commented: "Today the government, which had demanded compensation from the rescuers, left the decision to the tribunal and abandoned the courtroom."

Dariush Beigui, a former member of the Iuventa and one of the defendants, said he felt "relieved and sad at the same time:

"If prosecutors had examined the evidence at the beginning, they would never have been authorized to seize the Iuventa and we would have been spared seven years of stress. One eye is crying and the other one is laughing," Beigui said.

Sascha Girke, another former crew member and defendant, said the case should never have begun: "The Iuventa should never have been seized and people should not have been left to die," he said. "Now the court of Trapani has the chance to stop the toxic effect of this criminalization of solidarity, a situation that should never have been allowed."