MEXICO CITY (AP) — Mexican prosecutors on Thursday declared completely unfounded the U.S. case against a former defense secretary arrested on drug charges in the United States and then returned under pressure from the Mexican government.

Few had ever expected Mexico to really prosecute influential former Defense Secretary Salvador Cienfuegos. President Andrés Manuel López Obrador has relied more on the army than any other recent president, trusting it with everything from infrastructure projects to operating airports and trains.

Some thought Mexican prosecutors might dismiss the case on technical grounds of inadmissible evidence. But they went further than that, absolutely clearing Cienfuegos of accusations that he helped a drug cartel in return for bribes in a move that could mar Mexico’s already-bumpy relations with the United States in the post-Trump era.

In a surprisingly quick process, Mexico’s Attorney General’s Office announced that Cienfuegos presented evidence in five days that it said completely disproved what it described as a seven-year U.S. investigation of the now-retired general.

“The conclusion was reached that General Salvador Cienfuegos Zepeda never had any meeting with the criminal organization investigated by American authorities, and that he also never had any communication with them, nor did he carry out acts to protect or help those individuals,” the office said in a statement.

It said Cienfuegos had not been found to have any illicit or abnormal income, nor was any evidence found “that he had issued any order to favor the criminal group in question.”

All charges were dropped and Cienfuegos, who was never placed under arrest after he was returned by U.S. officials, is no longer under investigation.

Cienfuegos was arrested in Los Angeles in October, after he was secretly indicted by a federal grand jury in New York in 2019. He was accused of conspiring with the H-2 cartel in Mexico to smuggle thousands of kilos of cocaine, heroin, methamphetamine and marijuana while he was defense secretary from 2012 to 2018.

Prosecutors said intercepted messages showed that Cienfuegos accepted bribes in exchange for ensuring the military did not take action against the cartel and that operations were initiated against its rivals. He was also accused of introducing cartel leaders to other corrupt Mexican officials.

Under the pressure of Mexico’s implicit threats to restrict or expel U.S. agents, U.S. prosecutors dropped their case so Cienfuegos could be returned to Mexico and investigated under Mexican law.