LIMA (Reuters) - Peru’s president urged a speedy trial of his jailed predecessor Ollanta Humala on Friday, as an ongoing graft scandal tests the Andean nation’s political establishment and its judicial system.

Peru's President Pedro Pablo Kuczynski waits for the arrival of Chile's President Michelle Bachelet at the Government Palace in Lima, Peru July 7, 2017. REUTERS/Mariana Bazo

Peruvians had already seen one former president, Alberto Fujimori, jailed for corruption and human rights abuse years before Humala and his wife turned themselves in on Thursday pending a money laundering trial in which they deny wrongdoing.

But with Humala behind bars for up to 18 months while prosecutors prepare charges under the arrest order while a third former president, Alejandro Toledo, remains a fugitive, the Andean nation’s courts and politicians are under unprecedented scrutiny.

“Everyone has the right to efficient and rapid justice,” President Pedro Pablo Kuczynski said on local television, calling the news a tragic day for Humala’s family.

“We must fight against corruption, but fight with due process. What we cannot do is let ourselves be guided by the clamors of the mob,” he added.

Prosecutor German Juarez accuses Humala and his wife, Nadine Heredia, of taking $3 million of illegally obtained funds from Brazilian builder Odebrecht SA. Odebrecht admitted in December to paying bribes across Latin America, and Peru and Brazil have led the most aggressive corruption investigations to date.

The arrest order for Humala from Peruvian Judge Richard Concepcion came a day after former Brazilian President Luiz Inacio Lula da Silva was sentenced to nearly 10 years in prison for graft.

Toledo, believed to be in the United States, refused to turn himself in this year, after Concepcion ordered him jailed before a trial for allegedly taking a $20 million bribe from Odebrecht.

The scandal has caused many Peruvians to lose faith in politics.

“There is no one who really inspires confidence,” said office worker Lilian Díaz, 26.

Humala recast himself as a more moderate leftist like Lula to win the 2011 election, following an unsuccessful 2006 presidential bid as an ally of Venezuela’s late socialist President Hugo Chavez. Kuczynski came to power in 2016 as part of a regional shift to the political right.

While some Peruvians celebrated Humala’s jailing as an attack on impunity, others objected to the jailing without charges. Unlike Humala, Lula will remain free on appeal in Brazil and hopes to run for president next year.

“The news on an international level of Ollanta going to jail is bad for the country because his guilt has not yet been demonstrated,” said Cesar Alarcon, 51, a newspaper vendor.