PARIS — El Salvador-based stablecoin issuer Tether said it has frozen about US$4.2 billion of its crypto tokens over links to “illicit activity,” mostly in the past three years, as authorities around the world try to crack down on crypto-related crime.

The world’s largest stablecoin company, which has more than $180 billion of its dollar-pegged token in circulation, up from around $70 billion three years ago, is able to remotely freeze its tokens held in users’ crypto wallets when asked to do so by law enforcement.

Tether said this week it had helped the U.S. Justice Department freeze nearly $61 million worth of its tokens, called USDT, which were linked to “pig-butchering,” a form of fraud in which scammers form a personal…