EL CANTRI is a cheeky name for a housing project built for the poorest people in Jujuy, one of Argentina’s poorest provinces. The message is that its 15,000 inhabitants are no less entitled to comfort than residents of a posh gated community—known in Argentina as “countries”. A playground is equipped with dinosaur-shaped slides; a vast aquatic park has giant plastic sea lions. There is a full-scale replica of the Kalasasaya, a pre-Columbian temple, constructed out of breeze blocks. El Cantri has two factories, a clinic and a sports centre. On top of each house is a water tank stencilled with images of such popular heroes as Che Guevara and Eva Perón.

The settlement was built by Túpac Amaru, a social movement that for 17 years has provided housing and other services to 70,000 poor jujeños. The group thrived during the dozen years when Argentina was governed by the populist Kirchners: the late Néstor Kirchner and then his wife, Cristina Fernández de Kirchner. It was the third-largest employer in a remote agricultural province, in which 45% of the land is owned by just five companies, according to Carlos Aramayo at the National University of Jujuy. Túpac Amaru’s firebrand leader, Milagro Sala, is a celebrity. Pope Francis invited her to the Vatican in 2014.

Argentina’s elections last October brought about a change of regime, and a dramatic reversal of fortunes for Ms Sala and her movement. Gerardo Morales became the first non-Peronist governor of Jujuy in more than 30 years. He is an ally of the new centre-right president, Mauricio Macri, who is more likely to bet on free enterprise and new infrastructure than on left-wing social movements.

A clash was not long in coming. On December 10th, the day he took office, Mr Morales said that all co-operatives must register with the government in order to continue receiving money. Four days later Ms Sala and her supporters set up camp outside his office, demanding a meeting. Police arrested her on January 16th, saying she had incited violence. Since then the charges have mounted up: she is accused of fraud, extortion and conspiracy. Judges have ordered her to stay in prison while prosecutors investigate. It is not certain that the Túpac Amaru movement, named after the leader of an uprising against the Spanish in 1780, will survive the onslaught.

Joaquín Millón, Jujuy’s new anti-corruption investigator, alleges that more than half of the 1.3 billion pesos ($90m) funnelled by the national planning ministry through the provincial government and municipal authorities to Túpac Amaru from 2004 to 2015 has gone missing. The co-operative movement was contracted to build some 8,500 houses; after touring more than 30 projects, Mr Millón concluded that 2,300 were either incomplete or non-existent. Residents of El Cantri told Jujuy’s prosecutor, Mariano Miranda, that the movement illegally withheld title deeds to their homes and threatened to evict them if they did not support Ms Sala. She denies all the allegations.

The scandal raises awkward questions for Ms Fernández. Allegations have emerged linking her family to the scandal in Jujuy. In April a provincial deputy who is a former Túpac Amaru member told a judge that Ms Sala had delivered suitcases of cash to Ms Fernández’s son, Máximo Kirchner, in the Quinta de Olivos, the president’s official residence. They both deny it.

Human-rights groups have leapt to Ms Sala’s defence. Amnesty International criticised her initial arrest, saying she had been “criminalised for peacefully exercising her rights to freedom of expression and protest”. In March the UN’s Working Group on Arbitrary Detention urged Argentina’s government to justify her detention in writing. Mr Miranda bristles at the criticism. “They say that she’s a political prisoner, but she’s guaranteed due process,” he fumes. “Amnesty International hasn’t tried living near Milagro Sala.”

The beneficiaries of her work are beginning to lose faith. El Cantri’s pastel-painted terraced houses are showing signs of neglect. The clothing factory, opened in 2008 by Ms Fernández, supposedly employs 146 people, but just a handful could be seen during a recent tour. The water park, the community’s hub, has been drained. Since Túpac Amaru’s refusal to register, so too have its coffers. “Ninety percent of people here are against Milagro Sala,” says a man who lives close to El Cantri. “But that doesn’t mean they oppose Túpac Amaru.”

If the movement fails, Jujuy will need something to replace it. More than half of jujeños are poor and jobs are scarce. At three o’clock one recent afternoon the benefits queue at San Salvador de Jujuy’s post office stretched around the block. The last passenger train to Buenos Aires departed in 1993. Jujuy is among the ten provinces that are to benefit from Plan Belgrano, a scheme promoted by Mr Macri to reduce poverty, encourage enterprise and improve infrastructure in the north. “For decades Argentina turned its back on the north,” declared the president during a visit to Jujuy on May 16th. He pointedly promised to back projects “that aren’t synonymous with corruption”.

For residents of El Cantri, such schemes mean little compared with the tangible reality of their imperilled community. Daniela Calderón, a teacher at the newly opened primary school, bursts into tears as she watches her pupils playing happily in the playground. “They’re gradually dismembering our organisation,” she laments. “But we’ll be back, stronger.” Given Túpac Amaru’s monumental problems, that may prove a forlorn hope.