The mayor of a town in southern Italy famed for taking in migrants has been put under house arrest.
Domenico Lucano, mayor of Riace, has been detained over his alleged involvement in organising "marriages of convenience" for immigration purposes.
But a more serious charge of abuse of public funds was rejected by an investigating judge.
The arrest follows months of tougher migration enforcement from Italy's populist government.
The mayor, known as Mimmo, made headlines around the world for his unusual programme that welcomed migrants to the sparsely-populated town in Calabria, giving them abandoned homes and on-the-job training, in the hope that the new arrivals would rejuvenate the economy.
He started the programme in 1998 under a previous government, and since then hundreds of migrants have joined the small town of about 2,000 people.
The success of the programme, lauded by many as a model of integration, led to Mayor Lucano being named one of the world's 50 greatest leaders by Fortune magazine in 2016.
On Tuesday, he was arrested by Italy's financial police as part of an investigation into allegedly facilitating illegal migration.
Former integration minister Cécile Kyenge poured scorn on the arrest, arguing that the main thrust of the criminal investigation into the mayor had been abandoned. "So what's #MimmoLucano done wrong? Solidarity and humanity, perhaps?" she tweeted.
What are the charges?
The first charge detailed by prosecutors involves the arrangement of marriages of convenience to get around immigration regulations.
Prosecutors said they had wire-tapped Mr Lucano's phone and recorded at least one exchange in which the mayor appeared to suggest marriage as a solution to a woman's immigration problems, in a way they said could not be misunderstood.
One excerpt concerned a Nigerian migrant who had been denied residence three times, the statement said. Mr Lucano is reported to have said that marrying an Italian citizen was "the only way forward".
As mayor, Domenico Lucano is in charge of the town's civil registry.
In the excerpts he is said to refer to a similar wedding in the past, and his ability to arrange a ceremony quickly. He is also quoted offering to acquire an ID card to say the woman was a resident of Riace.
Prosecutors said he was also charged with allocating rubbish collection services to two companies without going through the required public tender process.
That charge may also have a connection to the town's migrant programme. The two companies were community co-operatives established "to provide work for the people of Riace and migrants", according to Italian newspaper La Repubblica.
His partner Tesfahun Lemlem faces the same charges and has been banned from living in the area.
No abuse of funds
However, the most serious allegation made against the mayor has been dropped.
The investigation had originally explored alleged mismanagement of public funds provided by the interior ministry. Prosecutors said that while the management of funds may have been disorderly, there was no evidence that any amount had been misappropriated.
Italy's populist government came to power in June with the head of the right-wing League party, Matteo Salvini, taking the role of interior minister. He has since pursued a series of anti-migration policies.
Mr Salvini reacted on Twitter by wondering what "all the good guys who want to fill Italy with immigrants" would say about the story.
He singled out writer Roberto Saviano, a vocal critic of Mr Salvini and a supporter of Riace's migration programme.
Writing on Facebook about the arrest, Mr Saviano said the government was "taking the first step towards the definitive transformation of Italy from a democracy to an authoritarian state."
Other government critics said the mayor's only crime had been one of humanity.
Mayor Lucano has yet to issue a statement on his arrest.