(Bloomberg) -- The head of a Mexican government unit in charge of auctioning goods seized from criminals said there was a pattern of irregularities within the agency, according to a letter announcing the resignation of the official.

Jaime Cardenas stepped down on Monday from his post as general director of Mexico’s Institute to Return Stolen Goods to the People, or INDEP, detailing a number of alleged corruption acts he’d found upon starting his post just three months ago. The agency was created by President Andres Manuel Lopez Obrador last year to auction seized goods, including cars and mansions, from illegal activities.

“At the beginning of our service, we found probable administrative irregularities,” Cardenas wrote in the letter, which was addressed to the president. Red flags included “jewelery mutilation, contracts favorable to companies and not to INDEP, and public servant conduct contrary to the rules.”

Complaints have already been made to the Attorney General’s Office and to the internal oversight body, the departing official said. He didn’t respond to phone calls requesting comment.

Cardenas also claimed that the agency is in a financially tough position, with over a billion pesos ($46 million) owed in labor compliance awards and additional debts to suppliers. In addition, he said, a 2 billion-peso ($91 million) transfer to the agency by the Attorney General’s Office has yet to be finalized.

“The situation is serious and urgent,” he wrote.

In a Wednesday morning press conference, Lopez Obrador said that the next head of the agency, Ernesto Prieto, will have to clean up when he takes office, after Cardenas wasn’t willing to do so.

“We always have to move forward,” he said. “This is David’s fight against Goliath.”

Mexico’s Finance Ministry didn’t immediately respond to requests for comment.

(Updates with details from the letter and Lopez Obrador comments throughout.)

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