A national security analyst with MSNBC called it quits at the network and has now joined Ukraine’s International Legion to fight the Russian invasion.

On Tuesday, MSNBC reported that snalyst Malcolm Nance had left the network at some point after Russia launched its invasion of Ukraine on Feb. 24. Nance announced he had joined the international band of volunteer soldiers, the Ukrainian equivalent of the French Foreign Legion.

Nance, who served in the U.S. Navy and the intelligence community for 30 years, is a prolific author on security matters like counterterrorism and insurgencies. He had worked at the network as a military affairs analyst since at least 2007, according to his LinkedIn account.

In an appearance on "The Reid Out" on Monday evening, Nance told host Joy Reid that he had set off for Ukraine after growing restless watching scenes of the war continue to filter, especially with former colleagues also serving alongside the Ukrainian military against Russia.

"I'm here to help this country fight what is essentially a war of extermination," said Nance, appearing on the network from an undisclosed location in Ukraine in his military uniform.

"Russia has brought it here and is mass murdering civilians," Nance continued. "And there are people here like me who are going to do something about it."

Nance was in Ukraine in the days leading up to the war and he continued to appear on the network as an analyst until at least Feb. 28. During his most recent appearance on Reid’s show, Nance was identified only as a “friend the show.” A spokesperson for MSNBC told The Hollywood Reporter that Nance was “not a contributor” at the network.

Foreigners have been fighting on both sides of the war in Ukraine since its earliest days in 2014 following Russia’s annexation of the Crimean Peninsula. Following Russia’s latest invasion, Ukraine’s President Volodomyr Zelensky created the unit on Feb. 27 and thousands of volunteers have flocked to join.

The U.S. does not forbid its citizens from fighting in Ukraine, but it has discouraged them from doing so. To date, a number of American military veterans like Nance have departed the U.S. to join the war.