(Bloomberg) -- The amount of cryptocurrency stolen through hacks and network exploits more than doubled to $1.38 billion in the first six months of the year, according to the blockchain intelligence firm TRM.

Five large attacks accounted for 70% of all the crypto that was stolen. Like in 2023 and other years, a small number of attacks constituted the majority of stolen funds.

The amount of crypto plundered this year, however, is still below the nearly $2 billion that was stolen in the first six months of 2022, the record year for crypto thievery.

Like this year, the prices of cryptocurrencies surged to record highs in the second half of 2021. TRM says that higher prices likely contribute to increased volumes of crypto theft.

The top ways hackers stole crypto was by gaining unauthorized access to private keys and seed codes, which are the cryptographic strings of numbers that allow one to access a crypto wallet.

The largest attack so far in 2024 stole over $300 million worth of Bitcoin, over 4,500 tokens, from Japanese crypto exchange DMM Bitcoin. The cause of the attack is still unknown.   

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