Authorities in Iran have seized tens of thousands of bitcoin mining machines claimed to have been using illegally subsidized electricity from state-run energy provider Tavanir.

According to a report by local media outlet Tasmin News Agency on Sunday, 45,000 mostly powerful application-specific integrated circuit (ASIC) machines were confiscated.

The machines had purportedly been consuming 95 megawatts per hour of electricity at a reduced rate, according to Tavanir's head Mohammad Hassan Motavalizadeh.

Earlier this month, Iranian authorities shut down 1,620 illegal cryptocurrency mining farms said to have collectively used 250 megawatts of electricity over the past 18 months, per a different news source.

The country's recent blackouts across major cities have been in part blamed on cryptocurrency mining, drawing the ire of officials who have sought a temporary stay on bitcoin (BTC, +4.08%) mining until further notice.

Cryptocurrency researcher Ziya Sadr told the Washington Post on Sunday miners had "nothing to do with the blackouts" claiming they only made up a "very small" percentage of overall electricity capacity in the country.

In July of last year, Iran penned a registration directive forcing miners to disclose their identities. It also forced them to disclose the size of their mining farms and their mining equipment type with the Ministry of Industry, Mines and Trade.