High-speed trader Doug Cifu said don't blame the computers for Monday's nearly 1,600-point plunge in the Dow Jones industrial average.

"The market functioned really well in a steep decline," Cifu, CEO of the high-speed trading giant Virtu, told CNBC on "Closing Bell."

"We had a lot of orders coming down through the pipes, and obviously we were taking on a lot of orders through the exchange," he said. "There was not a single self-help; there were no outs; there were no fast fingers that we saw. There were no busted trades, no repricing. It was just an avalanche of orders around 3 o'clock-ish."

Selling intensified on Wall Street on Monday afternoon, wiping out gains and knocking the index below 25,000. Cifu said his firm traded more than 11 billion shares Monday, a record for 2018.

Cifu said he did notice a "strong sell bias" among retail partners, but everything was working normally.

"The market functioned fine considering there was a 4 percent drop," he said, pointing out that the increased sell-offs that began last Friday, when the Dow dropped 665 points, might have triggered a lot of stop losses.

"So you have this kind of snowballing effect where people are taking their profits," Cifu said.

In fact, he said it's likely not a flash crash, a brief sharp plunge usually blamed on electronic trading, like the temporary 9 percent plunge in the Dow in May 2010.

"I didn't see stocks trading down to a penny, like you did in the flash crash," he said. "It was just an inordinate amount of orders and the sell orders out weighted the buy orders."

Whether or not the market has hit its bottom will be determined tomorrow, Cifu said.