The nine-year veteran is currently being evaluated and treated at a mental health facility after a number of incidents Saturday involving police and medical personnel, league sources told Paul Walsh of the Minneapolis Star Tribune.
Vikings executive director of player development and legal Les Pico told Minnestrista Police that Griffen hadn't been himself for weeks, so the team sent the player and his agent a letter Thursday informing him he wasn't allowed back at the team's facility until he underwent a mental health evaluation, ESPN's Courtney Cronin reports.
Griffen couldn't be placed on a health and welfare hold at the mental health facility by police because he hadn't threatened to do harm to himself or others, but the defensive end voluntarily agreed to go to the hospital, NFL Network's Tom Pelissero adds.
On Saturday, Griffen made several comments about people trying to kill him, referenced 777, and entered into a vehicle of someone he thought he knew at a gas station while leaving his behind, according to a police report obtained by Cronin.
His wife called police after he sped away from their home with another person while shirtless.
Griffen also reportedly threatened to "shoot someone" at the Hotel Ivy in downtown Minneapolis if he wasn't let into his room.
Vikings head coach Mike Zimmer ruled Griffen out for the team's Thursday night game against the Los Angeles Rams.
"The only thing we're concerned about with Everson isn't anything to do with football, it's about him getting better," Zimmer said. "I just hope the best for him. In the long run, he's a really good kid," he added.