Bitcoin investor Roger Ver has been arrested in Spain on charges of mail fraud and tax evasion.

The US Department of Justice is seeking his extradition for failing to report income on 131,000 bitcoins after renouncing US citizenship in 2014.

Ver is also accused of not paying taxes on $114 million worth of bitcoins and on $240 million from company-owned bitcoin sales in 2017.

This is not Ver's first run-in with the law, having previously served 10 months for selling explosives on eBay.

His defense cites intentions to comply with tax obligations and reliance on tax professionals, while prosecutors claim he provided false information to his tax firm.

Ver's arrest has sparked calls for clearer cryptocurrency regulations and enhanced consumer protections in the US digital asset markets.