According to NFL Network, questions about Griffen's mental health arose before last weekend, when he didn't play Sunday due to what the team said were personal reasons.
KSTP-TV's 5 Eyewitness News cited sources saying that Griffen threatened to shoot someone at the hotel. The Minneapolis Police Department report detailed the incident, with the name of the person making the threat redacted.
Vikings general manager Rick Spielman issued a statement that read, "We are aware of the situation involving Everson Griffen and certainly concerned by what we have heard. We are currently focused on Everson's well-being and providing the appropriate support for him and his family."
KSTP, citing the police report, indicated that hotel staffers moved to the back of the office as a man paced in the lobby. Police audio indicated that the man said he would shoot someone if he wasn't let into his room.
No arrests were made.
Griffen, 30, is in his ninth season with the Vikings, who made him a fourth-round draft pick in 2010 out of Southern California. In 123 games, including 65 starts, he has 62 sacks, one interception, and 10 forced fumbles. He logged a career-high 13 sacks last year.