Baton Rouge police shooting suspect identified as Gavin Eugene Long: reports
Gavin Long, aka 'Cosmo Setepenra' (YouTube)

A suspected gunman in the ambush that killed three Baton Rouge police officers on Sunday was a Missouri man who orchestrated the attack on his 29th birthday and may be linked with an anti-government group.

NBC and CBS News identified the gunman as Gavin Eugene Long of Kansas City, who was born on July 17, 1987. Long was killed in the attack. Local authorities said there is no longer an "active shooter" in the area.

Without mentioning him by name, the Wall Street Journal reported that Long was part of an anti-government group called the New Freedom Movement.

This story will be updated.

Update, 7:57 p.m. EST: CBS News reported, citing police sources, that Long -- a former Marine Corps member who left the service in 2010 -- rented a vehicle on July 12 and drove to Baton Rouge from Kansas City. He also attended the University of Alabama for a semester in 2012.

Long also reportedly went by the name "Cosmo Setepenra" online, and billed himself as a "Freedom Strategist," "Alpha Preneur," and "Mental Game Coach," among other titles. Buzzfeed reported that on his podcast, Long said he had been "blacklisted" by employers since leaving the Marines, even though he was discharged honorably.

"I also had a friend tell me that the government threatened him not associate to closely with me," said Long. "Essentially it’s isolation. They don’t want the spirit of courage to spread. Because their whole gimmick is fear."

In another installment, he insisted that he was not affiliated with any group, specifically rejecting ties to the Islamic State terrorist group.

"I'm affiliated with the spirit of justice -- nothing else," he said.

Watch Long's video, as posted online, below.