Keiko Fujimori, the leader of Peru’s political opposition and daughter of former autocrat Alberto Fujimori, has been detained as part of an investigation into alleged money laundering in her 2011 presidential campaign.

Prosecutors are investigating the origin of several large undeclared financial donations to Fujimori’s campaign and links to the Brazilian construction firm Odebrecht, which has been at the centre of Latin America’s biggest corruption scandal.

Fujimori’s detention on Wednesday comes just a week after a supreme court judge ordered her father, former president Alberto Fujimori, back to jail to complete a 25-year sentence for authorising death squads, overseeing rampant corruption and vote-rigging. Fujimori, 80, had been granted a medical pardon last year by former president Pedro Pablo Kuczynski.

“This detention is abusive and arbitrary,” said Keiko Fujimori’s lawyer, Giuliana Loza, who told journalists it took place when her client attended the chief prosecutor’s office to give testimony in the ongoing investigation.

Fujimori’s husband, Mark Vito, said she was the victim of “political persecution” and prosecutors had not found a single piece of evidence in an investigation lasting more than two years.

Fujimori’s supporters immediately gathered to protest outside the principal police station in downtown Lima. Images on social media showed a handcuffed Fujimori being transferred there from the prosecutor’s office.

Prosecutor José Domingo Pérez said he had asked for Fujimori to be detained for 10 days because of the risk she could escape. He said she had “set up and criminal organisation within her political party” that had “political power and, as a result, a level of influence and interference in legislative and judicial power”.

Along with Keiko Fujimori, 19 other people were ordered to be detained, among them the former heads of her presidential campaign in 2016, Jaime Yoshiyama and Augusto Bedoya.

A supporter of Keiko Fujimori holds a banner reading ‘Keiko is not alone’ outside a police facility in Lima on Wednesday. Photograph: Luka Gonzales/AFP/Getty Images

The prosecutors’ investigation has become known as the “cocktails” case because, it alleges, Fujimori’s political party laundered undeclared contributions through cocktail party fundraisers that supporters paid $300 to attend.

The investigation alleges more than 100 guests’ names were falsified to justify funds that could not be accounted for.

Fujimori, who leads the opposition party that dominates Peru’s congress, played a key role in the toppling of Pedro Pablo Kuczynski in March, but has seen her power tested by his replacement, Martín Vizcarra.

Last month, President Vizcarra reinforced public support for his anti-corruption campaign by challenging the opposition-dominated congress to back anti-graft reforms or face fresh elections.

“I think Keiko was screwed politically before this detention,” said the prominent political commentator and columnist Augusto Álvarez Rodrich. “But now it seems she is even more screwed on a judicial level.”

Accusations of corruption related to Odebrecht have tainted the last four presidents of Peru.

In March, Kuczynski resigned rather than face impeachment over allegations of corruption related to his links with the company.

Alejandro Toledo, who governed the country from 2001 to 2006, is fighting extradition from the United States on a charge that he took $20m in bribes from Odebrecht.

In July 2017, former president Ollanta Humala and his wife, Nadine Heredia, were jailed for nine months pending money laundering charges linked to campaign donations from the firm.

Fujimori’s detention was ordered by the same judge who jailed Humala and Heredia, moves which at the time were “celebrated and justified by members of Keiko Fujimori’s party, including herself,” said Álvarez.