"Due to extremely high demand, we have had to temporarily close our Buy Bitcoins service," Bit Innovate wrote. "Sourcing more. It will be open as soon possible."
BitFloor, the largest U.S. bitcoin exchange based in New York, warned of delays and technical issues with its website. Roman Shtylman, the founder of BitFloor, said his exchange saw its highest trading volume and highest number of users ever.
Shtylman said he was working on some changes to ensure smooth trading following Wednesday's frenzy.
"Everyone saw pain in a different way," he said.
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