Berkshire Hathaway Vice Chairman Charlie Munger, a longtime cryptocurrency skeptic, said digital currencies are a malicious combination of fraud and delusion.

"This is a very, very bad thing. The country did not need a currency that was good for kidnappers," Munger said in an interview with CNBC's Becky Quick. "There are people who think they've got to be on every deal that's hot. I think that's totally crazy. They don't care whether it's child prostitution or bitcoin."

The 98-year-old investor's comment came after a wild week for the industry. FTX filed for Chapter 11 bankruptcy protection after concerns over the company's financial health resulted in a run on the exchange and a plunge in the value of its native FTT token. Binance had backed out of a deal acquiring FTX after reports of mishandled customer funds and alleged U.S. government investigations into FTX.

"You are seeing a lot of delusion. Partly fraud and partly delusion. That's a bad combination," Munger said.

The price of bitcoin, the world' largest cryptocurrency, has fallen more than 60% this year to trade below $17,000, according to Coin Metrics.

"Good ideas, carried to wretched excess, become bad ideas," Munger said. "Nobody's gonna say I got some s*** that I want to sell you. They say – it's blockchain!"

Listen to the full interview with Munger on the Squawk Pod podcast.