The founding anchor of CNBC’s Squawk Box and co-anchor of Squawk On The Street died unexpectedly at his home last night, the financial news network reports. Haines, who was 65, was a  ”building block” of the network, CNBC President Mark Hoffman said. “With his searing wit, profound insight and piercing interview style, he was a constant and trusted presence in business news for more than 20 years. From the dot-com bubble to the tragic events of 9/11 to the depths of the financial crisis, Mark was always the unflappable pro. Mark loved CNBC and we loved him back. He will be deeply missed.”

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