About $761 million worth of cryptocurrency was stolen from exchanges in just the first half of 2018, Reuters reports, citing blockchain security firm CipherTrace.

That’s almost triple a roughly $266 million stolen from such exchanges last year, and CipherTrace warns 2018 exchange thefts could rise to as high as $1.5 billion by the time the year is done.

Just last month, two South Korean crypto exchanges were digitally robbed, with one attack netting up to $40 million and another set of hackers making out with about $31.6 million in digital funds, according to reports at the time. Unlike traditional banks, money stored at cryptocurrency exchanges often isn’t insured, and even investors who don’t do business with hacked exchanges can still be impacted, since reports of such heists often bring down cryptocurrency prices at least temporarily. The attackers behind such hacks can be sophisticated: North Korea has been accused of hacking exchanges to get funds in the face of sanctions limiting its role in the global economy.

Digital theft isn’t limited to cryptocurrency: In May, Banco de Chile, among the South American country’s largest banks, reportedly saw $10 million siphoned off by hackers who initiated bogus transactions through the international funds transfer system SWIFT amid a malware attack.