Mark Haines, co-anchor of CNBC's morning "Squawk on the Street" show and one of the business news network's most recognized faces, died unexpectedly on Tuesday evening, the network said. He was 65.
The network said he died in his home. It did not specify the cause of death.
Haines worked at CNBC for 22 years. He was the founding anchor of the "Squawk Box" morning show. In 2005, he started co-anchoring "Squawk In The Morning," a 9 a.m. to 11 a.m. show, with Erin Burnett, while "Squawk Box" was pushed to an earlier slot. Burnett recently left CNBC to host a general news show on CNN.
"He was a very dear friend, and a ferocious and fearless questioner," Burnett told CNBC on Wednesday.
CNBC President Mark Hoffman said Haines was "always the unflappable pro."
Traders on the floor of the New York Stock Exchange observed a spontaneous moment of silence when they learned of Haines' death, NYSE spokesman Richard Adamonis said.
"Mark was an outstanding professional and pioneer in business journalism, and we are proud that his legacy includes years of excellence in reporting from the NYSE," the exchange said in a statement.
"He was an authentic voice in business media," said Eric Jackson, who runs the hedge fund Ironfire Capital. "He resonated with so many people because he would speak out, and with opinion. Too often the media lets the corporate PR army and highly trained CEOs get their points across without question. He wouldn't let that happen."
Haines is also remembered for calling a bottom to the stock market decline on March 10, 2009, his first call of the recession. The Dow Jones Industrial Average never closed below its level of March 9.
Barry Ritholtz, head of the research firm Fusion IQ and frequent guest on CNBC, said Haines was "a no-nonsense straight shooter. He knew what questions to ask and how to ask them."
Ritholtz said that the biggest complaint about CNBC in the 1990s was that its anchors cheered on the stock-market bubble. He said the exception was Haines, who was always skeptical.
"He was trained as an attorney," Ritholtz said. "He brought that keen lawyer's eye to everything he did. It wasn't something often seen in the financial media."
Haines had a law degree from the University of Pennsylvania and was a member of the New Jersey State Bar Association, CNBC said.
Before joining CNBC, Haines worked as a news anchor at TV stations in Philadelphia, New York and Providence, R.I.
Haines is survived by his wife, Cindy, his son, Matt, and daughter, Meredith.
CNBC, which is owned by Comcast Corp., said funeral arrangements have yet to be made.
AP Business Writer Rachel Beck contributed to this story.