The team behind the cryptocurrency lending protocol Sonne Finance is offering a hacker an undisclosed bounty following a $20 million theft on Tuesday evening. 

Sonne Finance allows people to lend and borrow funds without the need for intermediaries such as banks. Several blockchain security companies tracked more than $20 million flowing out of the system on Tuesday evening in digital coins such as ether, the U.S.-dollar-backed USDC and others.

The developers confirmed that they had paused all markets and later published a postmortem on the attack explaining that the “attacker was able to exploit the protocol for ~$20 million.”

“We are ready to give bounty to exploiter as well as not to commit pursuing the issue further, in case of returning the funds,” Sonne Finance said, noting that it is “in contact with anyone that can help with recovering the funds.”

They discovered the attack within 25 minutes of it being executed, and some users were able to save about $6.5 million from being stolen through technical maneuvers. 

Since the attack, the hacker has been swapping the stolen cryptocurrency for bitcoin and other coins in a flurry of transactions. 

Law enforcement scrutiny of crypto thefts and the transfer to stolen funds has increased significantly in 2024, with several high profile market manipulators and operators facing charges.

Last month the man behind a $110 million theft from popular crypto platform Mango Markets was convicted in a federal court and is facing up to 30 years in prison. 

A Bulgarian woman behind a crypto scam also was given a four-year sentence in April and the cofounder of anonymizing cryptocurrency service Tornado Cash will spend about five years in prison following a conviction on Tuesday in the Netherlands.