HONG KONG (Reuters) - Poly Network said on Monday that almost all of the $610 million stolen this month in one of the biggest crypto heists had now been returned by the unknown person or persons behind the attack.

Cryptocurrency Platform Poly Network Regains Control of Assets Except for $33 Million in Stablecoin Tether

In a Twitter post, Poly Network said it had regained control of all the assets except for $33 million in stablecoin tether that had been frozen by the company that manages it.

The Hackers’ Plan

The hackers had previously said they did the attack for fun to expose a vulnerability in the platform’s digital contracts and it was always their plan to return the tokens.

Blockchain Analysts Speculate

Some blockchain analysts have speculated they just found it too difficult to launder so much stolen cryptocurrency.

The Hackers’ Fate

Poly Network announced the hack on Aug. 10 but said the perpetrators had started returning the digital coins the following day.

The Hacker’s Offer

The network also offered the hacker or hackers a $500,000 “bug bounty”.

The Outcome

(Reporting by Alun John; Editing by David Clarke)

This article is republished from Yahoo Sport.