Among rocket launchers, grenades and bullets, Venezuelan authorities also seized an unlikely technology from criminals during a prison raid this week: Bitcoin mining machines. 

In an operation to crack the South American country’s most powerful organized crime group Wednesday, 11,000 troops were used to raid the Tocorón prison in Aragua state, according to an official government statement. 

Weapons were found in the mission but authorities also grabbed Bitcoin miners, AFP reported Thursday. Videos posted on Twitter showed a building full of the machines. 

Interior and Justice Minister Remigio Ceballos was quoted by the news agency saying that it was a “successful operation that allowed us to strike a blow against criminal groups.”

The prison—which had been run by criminals for years— included facilities like a swimming pool and a mini zoo. Venezuelan prisons are notoriously overcrowded and dangerous

Wednesday’s operation was the first time Venezuelan authorities have targeted the feared Tren de Aragua, which is involved in everything from drug and human trafficking to extortion in its home country and others in the region. 

Mining machines are used to mint new coins and keep the Bitcoin blockchain secure. 

Those involved in the energy intensive process need to use a lot of electricity but are rewarded with new cryptocurrency, and the endeavor can be quite lucrative. A report from Coin Metrics earlier this year showed that Bitcoin miners collectively earned $184 million from transaction fees in just April through June. 

Wednesday’s raid isn’t the first time criminals in Latin America have been caught apparently wanting to mint cryptocurrency: the find comes just two weeks after Chilean cops found a drug trafficking ring in Santiago had a Bitcoin mining operation up and running.   

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