Iran’s Ministry of Industries, Mining and Trade issued operation licenses for 30 crypto mining centers in the country, the country’s Financial Tribue reported last Wednesday.

Citing data from the ministry’s website, the report says that Iran’s Semnan province received the largest amount of licenses, with six crypto mining farms now authorized to operate in the region. Alborz province has secured four such licenses, followed by Mazandaran, East Azarbaijan and Zanjan provinces. Tehran province, which houses the country’s capital, reportedly received only one license for operating a crypto mining center.

The ministry has also issued 2,579 establishment permits for new industrial crypto mining units across the country, with 305 of those secured by Zanjan province. Fars province and West Azerbaijan follow Zanjan with 262 and 247 permits, respectively.

According to the report, an operation license is mandatory for Iranian companies to start a legal crypto mining business. Eligible applicants should acquire establishment permits and set up their industrial unit within 12 months and then apply for the operation license.

The report notes that cryptocurrency mining is legal in Iran as miners are allowed to operate under rules approved by the government in July 2019. Despite the legal status of crypto mining in Iran, the government is actively fighting illegal crypto miners due to increasing pressure on the national power grid. According to the report, authorized crypto mining companies are required to pay much higher energy costs for mining cryptocurrencies like Bitcoin (BTC) than residential or other commercial customers.

The ministry did not immediately respond to Cointelegraph’s request for comment.

Related: Iran may reap upwards of $1 billion in annual Bitcoin mining revenues

The news comes after Iranian President Hassan Rouhani announced in late May a blanket ban on Bitcoin mining in the country until September as a measure to alleviate pressure on the national power grid. Subsequently, Iranian provincial police confiscated more than 7,000 mining rigs at a farm operating in the capital of Tehran last Tuesday. The crypto mining farm was referred to as the largest and most significant drain on the country’s energy usage.

According to the Iran Power Generation, Distribution and Transmission Company, more than 188,000 units of crypto mining equipment were seized over the past 12 months. These devices reportedly caused 180 trillion rials ($4.2 billion) in losses to the national grid and power distribution equipment.