A Salvadoran news outlet has reported that a computer and cryptocurrency expert critical of the country accepting Bitcoin as legal tender was arrested by local police and held for hours before being released.

According to multiple interviews conducted by La Prensa Gráfica, police in San Salvador arrested computer specialist Mario Gómez Wednesday without a warrant, seizing his phone and attempting to take possession of a computer from his mother Elena de Gomez. The National Civil Police, or PNC, released a statement saying Gómez’s detainment was related to an investigation for financial fraud. Otto Flores, Gómez’s lawyer, said authorities released Gómez later that afternoon.

"[Mario] participates a lot in forums, in events, on social networks and is critical of the government," said his mother. "If we see that the country is going backward, it is necessary to speak because it is a human right to express our opinions.”

Gómez has regularly posted on social media about his opposition to legislation set to make Bitcoin (BTC) legal tender in El Salvador on Sept. 7. His Twitter posts include allegations that individuals behind the government’s Bitcoin wallet “Chivo” may be associated with the same BTC address associated with the massive hack of Twitter in July 2020. He has also made No Al Bitcoin (No To Bitcoin) stickers available to his thousands of followers.

There have been at least two major protests in San Salvador since the nation’s Legislative Assembly passed a bill proposing Bitcoin be accepted as legal tender alongside the U.S. dollar. President Nayib Bukele initially announced he would be pursuing such a law at the Bitcoin 2021 conference in June but later added Salvadorans would have the choice not to use the cryptocurrency.

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Following news of his arrest, Gómez’s followers started a Twitter campaign to “Free Mario.” Steve Hanke, an economist at Johns Hopkins University, referred to the move by the PNC as “authoritarian police tactics in action.” Anabel Belloso, a member of the country’s Legislative Assembly, also implied the authorities were attempting to “invent charges” against Gómez.

“The arrest of Mario portrays the fragility of the government in terms of the implementation of the Bitcoin Law but confirms something even more dangerous,” said Héctor Silva, councilor of the mayor’s office of San Salvador. “They are willing to manipulate whatever institutions are necessary to push critical voices out of their way.”