(Bloomberg) -- A Mexican judge ordered the detention of a former cabinet minister facing corruption charges, in the highest profile arrest of a politician since Andres Manuel Lopez Obrador took office promising to stamp out corruption.

Rosario Robles, who was minister for social development and agrarian development from 2012 to 2018, is accused of participating in an embezzlement scandal that saw 5 billion pesos ($260 million) diverted from federal agencies during the presidency of Enrique Pena Nieto. She was sent to prison for two months as the investigation unfolds. The public prosecutor argued that she was a flight risk. Robles says she is innocent.

National TV networks on Tuesday morning showed video of Robles, a former head of the Mexico City government, in a black police SUV on her way to the San Martha women’s prison on the eastern edge of Mexico City.

AMLO, as the leftist leader is known, was elected a year ago partly on the back of promises to rid the nation of graft. Veronica Ortiz, a lawyer and co-host of a show on Mexico’s non-partisan Congress channel who has followed the nation’s politics for more than two decades, said she can’t recall another instance of a current or former cabinet official going to jail.

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“On the fight against corruption, this sends a signal that accusations that a judge believes have substance will be pursued,” she said.

In July prosecutors issued an arrest warrant for Emilio Lozoya, the former chief executive officer of national oil producer Petroleos Mexicanos, in connection to the purchase of a fertilizer plant that was allegedly overvalued. Lozoya became a fugitive after disobeying orders to appear before a judge. They also arrested Juan Ramon Collado, an attorney with ties to Pena Nieto, on on money-laundering charges.

To contact the reporter on this story: Eric Martin in Mexico City at emartin21@bloomberg.net

To contact the editors responsible for this story: Juan Pablo Spinetto at jspinetto@bloomberg.net, Bruce Douglas

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