Ed Schultz, the liberal firebrand and former MSNBC host who most recently anchored a show for a Russian-funded media organization, died on Thursday. He was 64.

Schultz's death was confirmed by RT America, the Russian-funded media outlet where he hosted "News With Ed."

"We at RT America are sad to announce the passing of Edward Andrew Schultz," the network said in a statement. "Ed Schultz passed quietly early morning on July 5 at his home in Washington, D.C. This announcement comes as a shock to all of us here at RT America."

WDAY-TV, where Schultz had once worked as sports director, reported that Schultz died of natural causes.

A longtime resident of Minnesota, Schultz distinguished himself from other liberal pundits with his gruff, blue collar style. His broadcast career took off with a radio show in Fargo, North Dakota, but he rose to national prominence at MSNBC, where he hosted a show for six years until it was canceled in 2015.

Schultz was hired by the network at the outset of Barack Obama's presidency, and -- true to his staunchly pro-labor ethos -- he used his program to drive up support for the effort to recall Wisconsin Gov. Scott Walker in 2012. But Schultz left MSNBC three years ago as the network reshuffled its programming lineup, ultimately landing at RT America in 2016. It was at the Russian-funded outlet where Schultz's career took a turn.

Once a strong critic of Vladimir Putin, Schultz turned dismissive of the allegations that the Russian government was involved in hacking the 2016 election, echoing the argument from many on the left that it's simply an excuse for Hillary Clinton's defeat. In 2017, a month in Donald Trump's presidency, Schultz even spoke on a panel at the annual Conservative Political Action Conference, an event he once compared to Nazi Germany.