Cramer says it's 'insane' and 'frightening' that crypto trading is influencing the stock market

Scott Mlyn | CNBC

CNBC's Jim Cramer said Thursday he's unsettled by the idea that highly volatile cryptocurrencies appear to be influencing trading in the U.S. stock market.

The Dow Jones Industrial Average, the S&P 500 and the tech-heavy Nasdaq were all higher early Thursday as bitcoin and other cryptos recovered. Bitcoin later came off its highs after the Treasury Department announced its support for more strict regulation on cryptocurrency transactions.

The major Wall Street benchmarks Wednesday all finished well off their worst levels as bitcoin mounted a comeback from its morning plunge of as much as 30% to more than three-month lows near $30,000.

With the intraday improvement in stocks on Wednesday likely tied to the afternoon bounce in the crypto market, Cramer said, "It's insane. It's insane."

Cramer's premarket comments on "Squawk on the Street" followed Wednesday's wild session in not only bitcoin but other cryptocurrencies, such as ether.